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Yang J, Lin J, Zhang W, Shen M, Wang Y, Xie J. Resveratrol-loaded pH-responsive Mesona chinensis polysaccharides-zein nanoparticles for effective treatment of ulcerative colitis. J Sci Food Agric 2024; 104:3992-4003. [PMID: 38323719 DOI: 10.1002/jsfa.13282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/09/2023] [Accepted: 01/08/2024] [Indexed: 02/08/2024]
Abstract
BACKGROUND Resveratrol (Res) is promising food functional factor with favorable antioxidant and anti-inflammatory properties, although its poor water solubility and low bioavailability limit extensive application. Therefore, in combination with another promising polysaccharide (Mesona chinensis polysaccharides, MCP), Res-loaded food nanocarriers (ResNPs) were developed to increase its water solubility, bioactivity and targeting properties. ResNPs were then applied to alleviate dextran sulfate sodium (DSS)-induced ulcerative colitis. RESULTS Resveratrol can be well encapsulated in MCP-based nanoparticles in an amorphous state, improving its water solubility. ResNPs showed pH-response controlled release behavior in the gastrointestinal tract and increased the enrichment of Res in the colon. In vivo experiments of ResNPs against DSS-induced ulcerative colitis (UC) revealed that ResNPs significantly improved UC symptoms, modulated intestinal inflammation and down-regulated oxidative stress levels compared to free Res. ResNPs also play an positive role with respect to inhibiting the mitogen-activated protein kinase pathway and promoting the expression of tight junction proteins. In addition, ResNPs improved the species composition and relative abundance of intestinal flora in UC mice, which effectively regulated the balance of intestinal flora and promoted the production of short-chain fatty acids. CONCLUSION These results suggest that MCP-based nanoparticles can effectively improve the solubility of resveratrol and enhance its in vivo bioactivity. Moreover, the present study also provides a new strategy for the prevention and treatment of UC with food polyphenol. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Jun Yang
- State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang, China
| | - Jieqiong Lin
- State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang, China
| | - Weidong Zhang
- State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang, China
| | - Mingyue Shen
- State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang, China
| | - Yuanxing Wang
- State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang, China
| | - Jianhua Xie
- State Key Laboratory of Food Science and Resources, Nanchang University, Nanchang, China
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2
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Wang X, Wei J, Zeng Y, Qian Y. Diesel soot combustion in air-NO environment: Evolution of functional groups on soot surfaces. Sci Total Environ 2024; 918:170579. [PMID: 38336061 DOI: 10.1016/j.scitotenv.2024.170579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 01/24/2024] [Accepted: 01/28/2024] [Indexed: 02/12/2024]
Abstract
It is inevitable for NO to be involved in the soot combustion in diesel particulate filters (DPFs), so giving full play to the NO oxidation activity is one of the most effective means to improve the DPF regeneration performance. In this work, based on the results of programmed temperature oxidation (TPO) experiments, Fourier transfer inference spectroscopy, and X-ray photoelectron spectroscopy, the evolution of surface functional groups was seriously analyzed to explore the soot oxidation mechanism. The results revealed that with the presence of NO in the air atmosphere, the concentration of -ONO2 groups showed an increasing trend in the early oxidation stage of 0-20 % oxidation degree (OD) and then slowly decreased during 20-80 % OD, while the variations in CH functional group concentration were directly related to the concentration NO in the air atmosphere. COO functional group is easy to decompose, and NO promotes COO's generation and decomposition. The sp3/sp2 hybrid ratio is strongly correlated with CO (carbon‑oxygen double bond), but the content of CO is also affected by the desorption of COO functional groups. It is worth noting that when the soot oxidation degree is at 50 %-80 % OD, CO groups are converted to CO functional groups.
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Affiliation(s)
- Xin Wang
- School of Automotive and Transportation Engineering, Hefei University of Technology, No. 93 Tunxi Road, Hefei 230009, China
| | - Jiangjun Wei
- School of Automotive and Transportation Engineering, Hefei University of Technology, No. 93 Tunxi Road, Hefei 230009, China.
| | - Yang Zeng
- School of Automotive and Transportation Engineering, Hefei University of Technology, No. 93 Tunxi Road, Hefei 230009, China
| | - Yejian Qian
- School of Automotive and Transportation Engineering, Hefei University of Technology, No. 93 Tunxi Road, Hefei 230009, China.
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3
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Ying Y, Liu D. Formation and Evolution of Soot in Ethylene Inverse Diffusion Flames in Ozone Atmosphere. Nanomaterials (Basel) 2023; 13:816. [PMID: 36903694 PMCID: PMC10005136 DOI: 10.3390/nano13050816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/20/2023] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
Ozone is a prospective additive for enhancing and controlling combustion under lean or very lean conditions, and reduces NOx and particulate matter emissions simultaneously. Typically, in studying the effects of ozone on combustion pollutants, the focus is on the final yield of pollutants, while its detailed effects on the soot formation process remain unknown. Here, the formation and evolution profiles of soot containing morphology and nanostructures in ethylene inverse diffusion flames with different ozone concentration additions were experimentally studied. The surface chemistry and oxidation reactivity of soot particles were also compared. The soot samples were collected by a combination of the thermophoretic sampling method and deposition sampling method. High-resolution transmission electron microscopy analysis, X-ray photoelectron spectroscopy and thermogravimetric analysis were applied to obtain the soot characteristics. The results showed that soot particles experienced inception, surface growth, and agglomeration in the ethylene inverse diffusion flame within a flame axial direction. The soot formation and agglomeration were slightly advanced since the ozone decomposition contributed to promoting the production of free radicals and active substances in the ozone added flames. The diameter of primary particles in the flame with ozone addition was larger. With the increase of ozone concentration, the content of soot surface oxygen increased and the ratio of sp2/sp3 decreased. Furthermore, the addition of ozone increased the volatile content of soot particles and improved soot oxidation reactivity.
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Affiliation(s)
- Yaoyao Ying
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
- Advanced Combustion Laboratory, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Dong Liu
- MIIT Key Laboratory of Thermal Control of Electronic Equipment, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
- Advanced Combustion Laboratory, School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
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4
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Liu Y, Wu S, Fan C, Wang X, Liu F, Chen H. Variations in surface functional groups, carbon chemical state and graphitization degree during thermal deactivation of diesel soot particles. J Environ Sci (China) 2023; 124:678-687. [PMID: 36182173 DOI: 10.1016/j.jes.2022.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 12/28/2021] [Accepted: 01/08/2022] [Indexed: 06/16/2023]
Abstract
The thermal deactivation of diesel soot particles exerts a significant influence on the control strategy for the regeneration of diesel particulate filters (DPFs). This work focused on the changes in the surface functional groups, carbon chemical state, and graphitization degree during thermal treatment in an inert gas environment at intermediate temperatures of 600°C, 800°C, and 1000°C and explore the chemical species that were desorbed from the diesel soot surface during thermal treatment using a thermogravimetric analyser coupled with a gas-chromatograph mass spectrometer (TGA-GC/MS). The surface functional groups and carbon chemical state were characterized using Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The graphitization degree was evaluated by means of Raman spectroscopy (RS). The concentrations of aliphatic C-H, C-OH, C=O, and O-C=O groups are reduced for diesel soot and carbon black when increasing the thermal treatment temperature, while the sp2/sp3 hybridized ratio and graphitization degree enhance. These results provide comprehensive evidence of the decreased reactivity of soot samples. Among oxygenated functional groups, the percentage reduction during thermal treatment is the largest for the O-C=O groups owing to its worst thermodynamic stability. TGA-GC/MS results show that the aliphatic and aromatic chains and oxygenated species would be desorbed from the soot surface during 1000°C thermal treatment of diesel soot.
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Affiliation(s)
- Ye Liu
- Institute for Transport Studies, University of Leeds, Leeds LS2 9JT, UK
| | - Sijin Wu
- Institute for Transport Studies, University of Leeds, Leeds LS2 9JT, UK
| | - Chenyang Fan
- Vehicle & Transportation Engineering Institute, Henan University of Science and Technology, Luoyang 471003, China.
| | - Xin Wang
- Vehicle & Transportation Engineering Institute, Henan University of Science and Technology, Luoyang 471003, China
| | - Fangjie Liu
- Vehicle & Transportation Engineering Institute, Henan University of Science and Technology, Luoyang 471003, China
| | - Haibo Chen
- Institute for Transport Studies, University of Leeds, Leeds LS2 9JT, UK
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Ma Z, Tsounis C, Toe CY, Kumar PV, Subhash B, Xi S, Yang HY, Zhou S, Lin Z, Wu KH, Wong RJ, Thomsen L, Bedford NM, Lu X, Ng YH, Han Z, Amal R. Reconstructing Cu Nanoparticle Supported on Vertical Graphene Surfaces via Electrochemical Treatment to Tune the Selectivity of CO 2 Reduction toward Valuable Products. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05431] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhipeng Ma
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Constantine Tsounis
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
- CSIRO Manufacturing, 36 Bradfield Road, Lindfield, New South Wales 2070, Australia
| | - Cui Ying Toe
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Priyank V. Kumar
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Bijil Subhash
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Shibo Xi
- Institute of Chemical & Engineering Sciences, Agency for Science, Technology and Research, 1 Pesek Road, Singapore 627833, Singapore
| | - Hui Ying Yang
- Pillar of Engineering Product Development, Singapore University of Technology and Design, 20 Dover Drive, Singapore 138682, Singapore
| | - Shujie Zhou
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Zeheng Lin
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Kuang-Hsu Wu
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Roong Jien Wong
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
- Cambridge Centre for Advanced Research and Education, 1 CREATE Way, Singapore 138602 Singapore
| | - Lars Thomsen
- Australian Synchrotron, ANSTO, 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Nicholas M. Bedford
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Xunyu Lu
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Yun Hau Ng
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong 999077, China
| | - Zhaojun Han
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
- CSIRO Manufacturing, 36 Bradfield Road, Lindfield, New South Wales 2070, Australia
- School of Mechanical and Manufacturing Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Rose Amal
- School of Chemical Engineering, The University of New South Wales, Kensington, New South Wales 2052, Australia
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6
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Pan M, Wang Y, Wei J, Huang H, Zhou X. Impact of carbon chain length of alcohols on the physicochemical properties and reactivity of exhaust soot. Sci Total Environ 2021; 799:149434. [PMID: 34371412 DOI: 10.1016/j.scitotenv.2021.149434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/25/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
Particle is the main pollutant in diesel engine exhaust, which seriously endangers human health and the atmospheric environment. The use of alcohol fuels in diesel engines can effectively reduce particle emissions, but alcohol fuels with different carbon chain lengths will affect the generation process of particles, which in turn changes the physicochemical properties and oxidation characteristics of the particles. Therefore, it is particularly important to study the properties of particle emitted by diesel engines fueling alcohol fuels with different carbon chain lengths. The physicochemical properties of soot emitted from commercial diesel engines were studied by thermogravimetric analyzer, HRTEM (high-resolution transmission electron microscopy), and XPS (X-ray photoelectron spectroscopy) in this paper, respectively. The diesel engine used alcohol-diesel blends of different carbon chain lengths with the same oxygen content as fuels, such as methanol/diesel blend (M10), n-butanol/diesel blend (NB25), and n-octanol/diesel blend (NO45), and pure diesel fuel was used as a reference. The results showed that the use of alcohols reduced the fractal dimension (Df) of particles, and the NB25 particles had the smallest Df. Moreover, the particles of blended fuels had smaller primary particle diameter (dp) compared to pure diesel. However, with the use of short-chain to long-chain alcohols, an increasing tendency of dp was observed. In terms of the nanostructure, as the use of short-chain to long-chain alcohols, the La (fringe length) increased, both the d (fringe separation distance) and Tf (fringe tortuosity) reduced, which was not favorable for the oxidation of the particles. In addition, in terms of oxygenated surface functional groups (SFGs), the CO group occupied a higher proportion in most working conditions relative to the groups of CO and COO. Further analysis showed that the dp and nanostructure had more influence on the oxidation behavior of soot than Df and oxygenated SFGs.
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Affiliation(s)
- Mingzhang Pan
- College of Mechanical Engineering, Guangxi University, Nanning 530004, China
| | - Yuke Wang
- College of Mechanical Engineering, Guangxi University, Nanning 530004, China
| | - Jiangjun Wei
- School of Automotive and Transportation Engineering, Hefei University of Technology, No.193 Tunxi Road, Hefei, China.
| | - Haozhong Huang
- College of Mechanical Engineering, Guangxi University, Nanning 530004, China.
| | - Xiaorong Zhou
- College of Mechanical Engineering, Guangxi University, Nanning 530004, China
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7
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Wei J, Wang Y. Effects of biodiesels on the physicochemical properties and oxidative reactivity of diesel particulates: A review. Sci Total Environ 2021; 788:147753. [PMID: 34020091 DOI: 10.1016/j.scitotenv.2021.147753] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 05/09/2021] [Accepted: 05/10/2021] [Indexed: 05/20/2023]
Abstract
Particulate emissions from the combustion of diesel have always been the main concern, especially in recent years, with continuously stringent particulate emission regulation for diesel engines. To alleviate the problem, biodiesel has been received great attention because of its being environment-friendly, widely available and renewable. The application of biodiesel in diesel engines changes the combustion process, thus varies physicochemical property of the particulate matter (PM) formed, which in turn influences the oxidative reactivity of soot particles. In view of this, it is particularly important to analyze soot particles from the diesel engine fueled with biodiesels. This review focus on the effects of biodiesels on the physicochemical properties of soot particles, such as surface morphology, nanostructure, active surface area, element composition, elemental and organic carbon contents, surface functional groups, sp2 and sp3 hybridizations, etc. The impact of engine operating conditions (i.e. engine load, engine speed, fuel injection timing, fuel injection pressure, exhaust gas recirculation, etc.) on characteristics of soot particles from diesel engines powered by biodiesel is also discussed. Whereafter, the relationships between soot physicochemical characteristics and soot oxidative reactivity are reviewed. Finally, the main conclusions are outlined as well as the proposed research work in the future.
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Affiliation(s)
- Jiangjun Wei
- School of Automotive and Transportation Engineering, Hefei University of Technology, Hefei, Anhui 230009, China.
| | - Yuncheng Wang
- School of Automotive and Transportation Engineering, Hefei University of Technology, Hefei, Anhui 230009, China
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8
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Le YTH, Youn JS, Moon HG, Chen XY, Kim DI, Cho HW, Lee KH, Jeon KJ. Relationship between Cytotoxicity and Surface Oxidation of Artificial Black Carbon. Nanomaterials (Basel) 2021; 11:nano11061455. [PMID: 34072737 PMCID: PMC8229741 DOI: 10.3390/nano11061455] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 04/20/2021] [Revised: 05/11/2021] [Accepted: 05/28/2021] [Indexed: 12/15/2022]
Abstract
The lacking of laboratory black carbon (BC) samples have long challenged the corresponding toxicological research; furthermore, the toxicity tests of engineered carbon nanoparticles were unable to reflect atmospheric BC. As a simplified approach, we have synthesized artificial BC (aBC) for the purpose of representing atmospheric BC. Surface chemical properties of aBC were controlled by thermal treatment, without transforming its physical characteristics; thus, we were able to examine the toxicological effects on A549 human lung cells arising from aBC with varying oxidation surface properties. X-ray photoelectron spectroscopy, as well as Raman and Fourier transform infrared spectroscopy, verified the presence of increased amounts of oxygenated functional groups on the surface of thermally-treated aBC, indicating aBC oxidization at elevated temperatures; aBC with increased oxygen functional group content displayed increased toxicity to A549 cells, specifically by decreasing cell viability to 45% and elevating reactive oxygen species levels up to 294% for samples treated at 800 °C.
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Affiliation(s)
- Yen Thi-Hoang Le
- Department of Environmental Engineering, Inha University, Incheon 22212, Korea; (Y.T.-H.L.); (H.-W.C.)
- Program in Environmental and Polymer Engineering, Inha University, Incheon 22212, Korea
| | - Jong-Sang Youn
- Department of Energy and Environmental Engineering, The Catholic University of Korea, 43 Jibong-ro, Bucheon-si 14662, Korea;
| | - Hi-Gyu Moon
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 53212, Korea; (H.-G.M.); (X.-Y.C.); (D.-I.K.)
| | - Xin-Yu Chen
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 53212, Korea; (H.-G.M.); (X.-Y.C.); (D.-I.K.)
- Department of Human and Environmental Toxicology, University of Science & Technology, Daejeon 34113, Korea
| | - Dong-Im Kim
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 53212, Korea; (H.-G.M.); (X.-Y.C.); (D.-I.K.)
| | - Hyun-Wook Cho
- Department of Environmental Engineering, Inha University, Incheon 22212, Korea; (Y.T.-H.L.); (H.-W.C.)
| | - Kyu-Hong Lee
- Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, Jeongeup 53212, Korea; (H.-G.M.); (X.-Y.C.); (D.-I.K.)
- Department of Human and Environmental Toxicology, University of Science & Technology, Daejeon 34113, Korea
- Correspondence: (K.-H.L.); (K.-J.J.)
| | - Ki-Joon Jeon
- Department of Environmental Engineering, Inha University, Incheon 22212, Korea; (Y.T.-H.L.); (H.-W.C.)
- Program in Environmental and Polymer Engineering, Inha University, Incheon 22212, Korea
- Correspondence: (K.-H.L.); (K.-J.J.)
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Goel V, Mishra SK, Pal P, Ahlawat A, Vijayan N, Jain S, Sharma C. Influence of chemical aging on physico-chemical properties of mineral dust particles: A case study of 2016 dust storms over Delhi. Environ Pollut 2020; 267:115338. [PMID: 32866861 DOI: 10.1016/j.envpol.2020.115338] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 06/27/2020] [Accepted: 07/29/2020] [Indexed: 05/17/2023]
Abstract
The physico-chemical properties of dust particles collected During Dust Storm (DDS) and After Dust Storm (ADS) events were studied using Scanning Electron Microscope coupled with Energy Dispersive X-ray Spectroscopy (SEM-EDS), X-ray Fluorescence Spectroscopy (XRF) and X-ray Photoelectron Spectroscopy (XPS). Morphological and compositional change in dust particles were observed as they react with the anthropogenic pollutants present in the urban environment. The calcite rich particles were observed to transform into calcium chloride, calcium nitrate, and calcium sulfate on reacting with the chlorides, nitrates, and sulfates present in the urban atmosphere. The frequency distributions of Aspect Ratio (AR) for the DDS and ADS particles were observed to be bimodal (mode peaks at 1.2 and 1.5) and monomodal (mode peak at 1.1), respectively. The highly irregular shaped solid dust particles were observed to transform into nearly spherical semisolid particles in the urban environment. XPS analysis confirms the high concentration of oxides, nitrates, and chlorides at the surface of ADS samples which show the signatures of mineral dust particles aging. Species with a high value of imaginary part of refractive index (like Cr metal, Fe metal, Cr2O3, FeO, Fe2O3) were observed at the surface of dust particles. At 550 nm wavelength, the light-absorbing potential of the observed species along with black carbon (BC) was found to vary in the order; Cr metal > Fe metal > Cr2O3> FeO > BC > Fe2O3> FeOOH. The presence of the aforementioned species on the surface of ADS particles will tremendously affect the particle optical and radiative properties compared to that of DDS particles. The present work could reduce the uncertainty in the radiation budget estimations of mineral dust and assessment of their climatic impacts over Delhi.
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Affiliation(s)
- Vikas Goel
- CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, 110012, India; Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India
| | - Sumit K Mishra
- CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, 110012, India; Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India.
| | - Prabir Pal
- CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, 110012, India; Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India; CSIR-Central Glass and Ceramic Research Institute, 196, Raja S. C. Mullick Road, Kolkata, 700032, India
| | - Ajit Ahlawat
- CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, 110012, India; Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India; TROPOS, Leibniz Institute for Tropospheric Research, Permoserstraße, Leipzig, 04318, Germany
| | - Narayanasamy Vijayan
- CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, 110012, India; Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India
| | - Srishti Jain
- CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, 110012, India; Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India
| | - Chhemendra Sharma
- CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi, 110012, India; Academy of Scientific and Innovative Research (AcSIR), Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India
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Baldelli A, Trivanovic U, Sipkens TA, Rogak SN. On determining soot maturity: A review of the role of microscopy- and spectroscopy-based techniques. Chemosphere 2020; 252:126532. [PMID: 32229356 DOI: 10.1016/j.chemosphere.2020.126532] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 03/13/2020] [Accepted: 03/16/2020] [Indexed: 05/23/2023]
Abstract
Incomplete combustion is the main source of airborne soot, which has negative impacts on public health and the environment. Understanding the morphological and chemical evolution of soot is important for assessing and mitigating the impact of soot emissions. Morphological and chemical structures of soot are commonly studied using microscopy or spectroscopy, and the best technique depends on the parameter of interest and the stage of soot formation considered (i.e., maturity). For the earliest stages of soot formation, particles exhibit simple morphology yet complex and reactive chemical composition, which is best studied by spectroscopic techniques sensitive to the large number of soot precursor species. The only microscope that can offer some morphological information at this stage is the scanning probe microscopy, which can image single polycyclic aromatic hydrocarbons, the precursors of soot. A broader range of types of spectrometers and microscopes can be used by increasing the soot maturity. Mature soot is primarily carbon, and exhibits complex fractal-like morphology best studied with electron microscopy and techniques sensitive to thin oxide or organic coatings. Each characterization technique can target different morphological and chemical properties of soot, from the early to the late stage of its formation. Thus, a guideline for the selection of the appropriate technique can facilitates studies on environmental samples involving the presence of soot.
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Affiliation(s)
- Alberto Baldelli
- Department of Mechanical Engineering, University of British Columbia, 6250 Applied Science Ln #2054, Vancouver, BC, V6T 1Z4, Canada.
| | - Una Trivanovic
- Department of Mechanical Engineering, University of British Columbia, 6250 Applied Science Ln #2054, Vancouver, BC, V6T 1Z4, Canada
| | - Timothy A Sipkens
- Department of Mechanical Engineering, University of British Columbia, 6250 Applied Science Ln #2054, Vancouver, BC, V6T 1Z4, Canada
| | - Steven N Rogak
- Department of Mechanical Engineering, University of British Columbia, 6250 Applied Science Ln #2054, Vancouver, BC, V6T 1Z4, Canada
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Chen WQ, Zhang SM, Qiu J. Surface analysis and corrosion behavior of pure titanium under fluoride exposure. J Prosthet Dent 2020; 124:239.e1-239.e8. [PMID: 32402439 DOI: 10.1016/j.prosdent.2020.02.022] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 02/18/2020] [Accepted: 02/18/2020] [Indexed: 12/13/2022]
Abstract
STATEMENT OF PROBLEM The corrosive effects of oral fluoride products on titanium have been reported, and chronic fluorosis, which causes hyperfluoemia, is one of the world's health problems. Nevertheless, the relationship between high serum fluoride and corrosion on the titanium surface, which might have adverse effects on titanium implant osseointegration, has not been elucidated. PURPOSE The purpose of this in vitro study was to investigate the corrosion behavior of pure titanium exposed to high serum fluoride with different pH values based on surface analysis. MATERIAL AND METHODS Pure titanium specimens, exposed to different electrolytes with 0.04 and 0.4 ppm NaF at pH 7.3 and 5.0 values, were examined for surface microstructure by using scanning electron microscopy (SEM) and for surface element composition with X-ray photoelectron spectroscopy (XPS). The corrosion behavior and metal ion release of specimens immersed in the Hanks' balanced salt solution (HBSS) containing 0.04 and 0.4 ppm serum fluoride concentrations (NaF) at 7.3 and 5.0 pH values were measured by electrochemical impedance spectroscopy (EIS) and inductively coupled plasma atomic emission spectrometry (ICP-AES). RESULTS Pitting holes were observed on pure titanium surfaces exposed to high serum fluoride. The surfaces became rougher with the increase of serum fluoride concentration, especially under acidic conditions. XPS analysis revealed a reduction of dominant titanium dioxide (TiO2) on the pure titanium surface under serum fluoride exposure, corresponding to an increase in the relative level of F. EIS data showed an active corrosion behavior of pure titanium exposed to high serum fluoride and gradually decreased corrosion resistance with increasing concentration of serum fluoride, which was more severe under acidic conditions. The release of titanium ions was also induced by high serum fluoride and acidic conditions. CONCLUSIONS High serum fluoride had a negative influence on the corrosion behavior of pure titanium. The titanium oxide film barrier could be broken down in the fluoride ions condition, and the corrosion resistance of pure titanium decreased with the increasing concentration of serum fluoride. The increased corrosion susceptibility of pure titanium accelerated the release of titanium ions after exposure to high serum fluoride; this was more pronounced in an acidic environment.
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Affiliation(s)
- Wan-Qing Chen
- Graduate student, Department of Oral Implantology, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, PR China
| | - Song-Mei Zhang
- Resident, Department of General Dentistry, Eastman Institute for Oral Health, University of Rochester, Rochester, NY
| | - Jing Qiu
- Professor, Department of Oral Implantology, Affiliated Hospital of Stomatology, Jiangsu Key Laboratory of Oral Disease, Nanjing Medical University, Nanjing, PR China.
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12
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Liu Y, Zhang Q, Wu B, Li X, Ma F, Li F, Gu Q. Hematite-facilitated pyrolysis: An innovative method for remediating soils contaminated with heavy hydrocarbons. J Hazard Mater 2020; 383:121165. [PMID: 31522067 DOI: 10.1016/j.jhazmat.2019.121165] [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] [Received: 05/22/2019] [Revised: 09/04/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
As a recalcitrant fraction of petroleum, heavy hydrocarbons (including aromatics, resins, and asphaltenes) can remain in contaminated soils even after decades of weathering, thereby causing serious harm to the soil ecosystem and human health. Pyrolysis is a promising technique for remediating petroleum-contaminated soil. However, this technique still presents some drawbacks, such as high energy consumption and damage to soil properties. Therefore, an innovative method using hematite (Fe2O3) for the catalytic pyrolysis of weathered petroleum-contaminated soil was developed in this study. Compared with soil pyrolyzed without Fe2O3 at 400 °C for 30 min, the residual concentrations of aromatics, resins, and asphaltenes in soil pyrolyzed with 5.0% Fe2O3 were reduced by 67.8%, 52.3%, and 67.9%, respectively. After pyrolysis with 5.0% Fe2O3, the water-holding capacity of soil was considerably increased and the soil became darker and rougher. Scanning electron microscopy analysis showed that many small holes occurred on the surface of the pyrolytic soil. X-ray photoelectron spectrometer analysis showed that a thin layer of graphitic C was formed and deposited on the surface of the pyrolytic soil. We also observed that the wheat germination percentage and biomass yield in the soil pyrolyzed with 5.0% Fe2O3 were even higher than those in clean soil.
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Affiliation(s)
- Yuqin Liu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Qian Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Bin Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Xiaodong Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Fujun Ma
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Fasheng Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Qingbao Gu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China.
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13
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Affiliation(s)
- Yuanchun Zhang
- School of Earth and EnvironmentAnhui University of Science and Technology Huainan China
| | - Hanxu Li
- School of Chemical EngineeringAnhui University of Science and Technology Huainan China
| | - Shengtao Gao
- School of Chemical EngineeringAnhui University of Science and Technology Huainan China
| | - Yan Geng
- School of Earth and EnvironmentAnhui University of Science and Technology Huainan China
| | - Chengli Wu
- School of Chemical EngineeringAnhui University of Science and Technology Huainan China
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14
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Zhang Y, Li H, Wu C. Study on distribution, chemical states and binding energy shifts of elements on the surface of gasification fine ash. Res Chem Intermed 2019. [DOI: 10.1007/s11164-019-03824-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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15
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Pattammattel A, Leppert VJ, Forman HJ, O’Day PA. Surface characterization and chemical speciation of adsorbed iron(iii) on oxidized carbon nanoparticles. Environ Sci Process Impacts 2019; 21:548-563. [PMID: 30702742 PMCID: PMC6426675 DOI: 10.1039/c8em00545a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Carbonaceous nanomaterials represent a significant portion of ultra-fine airborne particulate matter, and iron is the most abundant transition metal in air particles. Owing to their high surface area and atmospheric oxidation, carbon nanoparticles (CNP) are enriched with surface carbonyl functional groups and act as a host for metals and small molecules. Using a synthetic model, concentration-dependent changes in the chemical speciation of iron adsorbed on oxidized carbon surfaces were investigated by a combination of X-ray and electron microscopic and spectroscopic methods. Carbon K-edge absorption spectra demonstrated that the CNP surface was enriched with carboxylic acid groups after chemical oxidation but that microporosity was unchanged. Oxidized CNP showed a high affinity for sorption of Fe(iii) from solution (75-95% uptake) and spectroscopic measurements confirmed a 3+ oxidation state of Fe on CNP irrespective of surface loading. The bonding of adsorbed Fe(iii) at variable loadings was determined by iron K-edge X-ray absorption spectroscopy. At low loadings (3 and 10 μmol Fe m-2 CNP), mononuclear Fe was octahedrally coordinated to oxygen atoms of carboxylate groups. As Fe surface coverage increased (21 and 31 μmol Fe m-2 CNP), Fe-Fe backscatters were observed at interatomic distances indicating iron (oxy)hydroxide particle formation on CNP. Electron-donating surface carboxylate groups on CNP coordinated and stabilized mononuclear Fe(iii). Saturation of high-affinity sites may have promoted hydroxide particle nucleation at higher loading, demonstrating that the chemical form of reactive metal ions may change with surface concentration and degree of CNP surface oxidation. Model systems such as those discussed here, with controlled surface properties and known chemical speciation of adsorbed metals, are needed to establish structure-activity models for toxicity assessments of environmentally relevant nanoparticles.
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Affiliation(s)
- Ajith Pattammattel
- School of Natural Sciences and Sierra Nevada Research Institute, University of California, Merced, California, USA
- Corresponding authors ,
| | - Valerie J. Leppert
- School of Engineering, University of California, Merced, California, USA
| | - Henry Jay Forman
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
| | - Peggy A. O’Day
- School of Natural Sciences and Sierra Nevada Research Institute, University of California, Merced, California, USA
- Corresponding authors ,
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16
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Elmes M, Gasparon M. Sampling and single particle analysis for the chemical characterisation of fine atmospheric particulates: A review. J Environ Manage 2017; 202:137-150. [PMID: 28732276 DOI: 10.1016/j.jenvman.2017.06.067] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 04/30/2017] [Accepted: 06/29/2017] [Indexed: 06/07/2023]
Abstract
To better understand the potential environmental and human health impacts of fine airborne particulate matter (APM), detailed physical and chemical characterisation is required. The only means to accurately distinguish between the multiple compositions in APM is by single particle analysis. A variety of methods and instruments are available, which range from filter-based sample collection for off-line laboratory analysis to on-line instruments that detect the airborne particles and generate size distribution and chemical data in real time. There are many reasons for sampling particulates in the ambient atmosphere and as a consequence, different measurement strategies and sampling devices are used depending on the scientific objectives and subsequent analytical techniques. This review is designed as a guide to some of the techniques available for the sampling and subsequent chemical analysis of individual inorganic particles.
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Affiliation(s)
- Michele Elmes
- School of Earth and Environmental Sciences, University of Queensland, Australia
| | - Massimo Gasparon
- School of Earth and Environmental Sciences, University of Queensland, Australia; National Institute of Science and Technology on Mineral Resources, Water and Biodiversity (INCT-Acqua), Brazil.
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17
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Chowdhury AKMRH, Tan B, Venkatakrishnan K. Fibroblast-Cytophilic and HeLa-Cytotoxic Dual Function Carbon Nanoribbon Network Platform. ACS Appl Mater Interfaces 2017; 9:19662-19676. [PMID: 28530092 DOI: 10.1021/acsami.7b04819] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [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: 06/07/2023]
Abstract
Carbon nanomaterials have emerged as a promising material in cancer diagnosis and therapy. Carbon nanomaterials/nanostructures (C-C molecular structure) act as a carrier/skeleton and require further surface modification through functionalization with chemicals or biomolecules to attain cell response. We report the synthesis of a novel carbon nanoribbon network (CNRN) platform that possesses a combination of C-C and C-O bond architecture. The bioactive CNRN showed enhanced ability for cell adhesion. Most importantly, it induced opposite cell responses from healthy cells and cancerous cells, cytophilic to fibroblasts but cytotoxic to HeLa cells. Ultrafast laser ionization under ambient conditions transforms nonbioresponsive C-C bond of graphite to C-C and C-O bonds, forming a self-assembled CNRN platform. The morphology, nanochemistry, and functionality on modulating fibroblast and HeLa adhesion and proliferation of the fabricated CNRN platforms were investigated. The results of in vitro studies suggested that the CNRN platforms not only attracted but also actively accelerated the adhesion and proliferation of both fibroblasts and HeLa cells. The proliferation rate of fibroblasts and HeLa cells is 91 and 98 times greater compared with that of a native graphite substrate, respectively. The morphology of the cells over a period of 24 to 48 h revealed that the CNRN platform induced an apoptosis-like cytotoxic function on HeLa cells, whereas fibroblasts experienced a cytophilic effect and formed a tissuelike structure. The degree of cytotoxic or cytophilic effect can be further enhanced by adjusting parameters such as the ratio of C-C bonds to C-O bonds, the nanoribbon width, and the nanovoid porosity of the CNRN platforms, which could be tuned by careful control of laser ionization. In a nutshell, for the first time, pristine carbon nanostructures free from biochemical functionalization demonstrate dual function, cytophilic to fibroblast cells and cytotoxic to HeLa cells.
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Affiliation(s)
| | | | - Krishnan Venkatakrishnan
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital , Toronto, Ontario M5B 1W8, Canada
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18
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Külah E, Marot L, Steiner R, Romanyuk A, Jung TA, Wäckerlin A, Meyer E. Surface chemistry of rare-earth oxide surfaces at ambient conditions: reactions with water and hydrocarbons. Sci Rep 2017; 7:43369. [PMID: 28327642 PMCID: PMC5361147 DOI: 10.1038/srep43369] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/23/2017] [Indexed: 11/12/2022] Open
Abstract
Rare-earth (RE) oxide surfaces are of significant importance for catalysis and were recently reported to possess intrinsic hydrophobicity. The surface chemistry of these oxides in the low temperature regime, however, remains to a large extent unexplored. The reactions occurring at RE surfaces at room temperature (RT) in real air environment, in particular, in presence of polycyclic aromatic hydrocarbons (PAHs), were not addressed until now. Discovering these reactions would shed light onto intermediate steps occurring in automotive exhaust catalysts before reaching the final high operational temperature and full conversion of organics. Here we first address physical properties of the RE oxide, nitride and fluoride surfaces modified by exposure to ambient air and then we report a room temperature reaction between PAH and RE oxide surfaces, exemplified by tetracene (C18H12) on a Gd2O3. Our study evidences a novel effect – oxidation of higher hydrocarbons at significantly lower temperatures (~300 K) than previously reported (>500 K). The evolution of the surface chemical composition of RE compounds in ambient air is investigated and correlated with the surface wetting. Our surprising results reveal the complex behavior of RE surfaces and motivate follow-up studies of reactions between PAH and catalytic surfaces at the single molecule level.
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Affiliation(s)
- Elçin Külah
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Laurent Marot
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Roland Steiner
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Andriy Romanyuk
- Glas Trösch AG, Industriestrasse 29, 4922 Bützberg, Switzerland
| | - Thomas A Jung
- Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Aneliia Wäckerlin
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland.,Laboratory for Thin Films and Photovoltaics, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Ernst Meyer
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
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19
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Affiliation(s)
- Andrew P. Ault
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jessica L. Axson
- Department
of Environmental Health Sciences, University of Michigan, Ann Arbor, Michigan 48109, United States
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20
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Li G, Yu L, Hu H, Zhu Q, Wang Y, Yu Y. Carbon-Infused MoS2 Supported on TiO2 Nanosheet Arrays for Intensified Anodes in Lithium Ion Batteries. Electrochim Acta 2016; 212:59-67. [DOI: 10.1016/j.electacta.2016.06.155] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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21
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22
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Deng S, Shu Y, Li S, Tian G, Huang J, Zhang F. Chemical forms of the fluorine, chlorine, oxygen and carbon in coal fly ash and their correlations with mercury retention. J Hazard Mater 2016; 301:400-6. [PMID: 26410268 DOI: 10.1016/j.jhazmat.2015.09.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/14/2015] [Accepted: 09/15/2015] [Indexed: 05/27/2023]
Abstract
Fly ashes recovered from the particulate control devices at six pulverized coal boiler unites of China, are studied using an X-ray photoelectron spectroscopy (XPS) with a particular focus on the functionalities of fluorine (F), chlorine (Cl), carbon and oxygen on fly ash. It is found that the inorganic forms of F and Cl are predominant on the ash surface in comparison with their organics, and the proportion of organic Cl is relatively higher than that of organic F. Similar results are also obtained in the bulk by correlating the F and Cl contents with those of the unburnt carbon and other compositions in ash. Strong correlations of mercury retention with surface carbon-oxygen functional groups indicate that the C=O, OH/C-O and (O-C=O)-O on surface are of significant importance for mercury retention in fly ash. Their surface concentrations are related to coal type. The presence of Cl in fly ash helps with mercury retention. No obvious effect of F is observed.
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Affiliation(s)
- Shuang Deng
- State Key Laboratory of Environmental Criteria and Risk Assessment, China; Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yun Shu
- Research Academy of Environmental Sciences, Beijing 100012, China
| | - Songgeng Li
- State Key Laboratory of Multi-phase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Gang Tian
- Research Academy of Environmental Sciences, Beijing 100012, China
| | - Jiayu Huang
- Research Academy of Environmental Sciences, Beijing 100012, China
| | - Fan Zhang
- Research Academy of Environmental Sciences, Beijing 100012, China.
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23
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Zhao F, Vrajitoarea A, Jiang Q, Han X, Chaudhary A, Welch JO, Jackman RB. Graphene-Nanodiamond Heterostructures and their application to High Current Devices. Sci Rep 2015; 5:13771. [PMID: 26350107 PMCID: PMC4563554 DOI: 10.1038/srep13771] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 07/27/2015] [Indexed: 12/26/2022] Open
Abstract
Graphene on hydrogen terminated monolayer nanodiamond heterostructures provides a new way to improve carrier transport characteristics of the graphene, offering up to 60% improvement when compared with similar graphene on SiO2/Si substrates. These heterostructures offers excellent current-carrying abilities whilst offering the prospect of a fast, low cost and easy methodology for device applications. The use of ND monolayers is also a compatible technology for the support of large area graphene films. The nature of the C-H bonds between graphene and H-terminated NDs strongly influences the electronic character of the heterostructure, creating effective charge redistribution within the system. Field effect transistors (FETs) have been fabricated based on this novel herterostructure to demonstrate device characteristics and the potential of this approach.
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Affiliation(s)
- Fang Zhao
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Andrei Vrajitoarea
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Qi Jiang
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Xiaoyu Han
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Aysha Chaudhary
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Joseph O Welch
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - Richard B Jackman
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
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24
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Lupi L, Kastelowitz N, Molinero V. Vapor deposition of water on graphitic surfaces: Formation of amorphous ice, bilayer ice, ice I, and liquid water. J Chem Phys 2014; 141:18C508. [DOI: 10.1063/1.4895543] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Laura Lupi
- Department of Chemistry, The University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, USA
| | - Noah Kastelowitz
- Department of Chemistry, The University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, USA
| | - Valeria Molinero
- Department of Chemistry, The University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, USA
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25
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Guo L, Hu Y, Hu Q, Lin J, Li C, Chen J, Li L, Fu H. Characteristics and chemical compositions of particulate matter collected at the selected metro stations of Shanghai, China. Sci Total Environ 2014; 496:443-452. [PMID: 25105755 DOI: 10.1016/j.scitotenv.2014.07.055] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 04/25/2014] [Accepted: 07/08/2014] [Indexed: 05/20/2023]
Abstract
A campaign was conducted to assess and compare the air quality at the different metro platforms at Shanghai City, focusing on particulate matter (PM) levels, chemical compositions, morphology and mineralogy, as well as species of iron. Our results indicated that the average PM₂.₅ concentrations for the three metro lines were 177.7 μg/m(3), 105.7 μg/m(3) and 82.5 μg/m(3), respectively, and the average PM1 concentrations for the three lines were 122.3 μg/m(3), 84.1 μg/m(3) and 59.6 μg/m(3), respectively. Fe, Mn, Cr, Cu, Sr, Ba and Pb concentrations in all of the sampling sites were significantly higher than that in the urban ambient air, implicating that these trace metals may be associated with the metro systems working. Individual airborne dusts were studied for morphology and mineralogy characteristics. The results revealed that the presence of most individual particles were with no definite shape and most of them were with a large metal content. Furthermore, Fe-rich particles had significantly higher abundance in the metro systems, which were more frequently encountered in the underground lines than the aboveground line. The 2D distribution map of an interested Fe-rich particle showed an uneven Fe distribution, implying that a hollow or core of other substance exists in the particle center during the formation process. Cluster analysis revealed that Fe-rich particles were possibly a mixture of Fe species. Fitting of X-ray absorption near-edge fine structure spectra (XANES) showed the main iron species within the particles collected from the three contrasting metro lines of Shanghai to be hematite, magnetite, iron-metal and mineral Fe. Hematite and mineral Fe were all found in three lines, while magnetite only existed in aboveground metro line. Iron-metal was determined in both the older and younger underground lines, based on the X-ray diffraction (XRD) analysis. As diverse Fe species have different physical-chemical characteristics and toxicity, the speciation of Fe-containing metro particles is important in the context of public health and control measures.
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Affiliation(s)
- Li Guo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Yunjie Hu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Qingqing Hu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Jun Lin
- Key Laboratory of Nuclear Analysis Techniques, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Chunlin Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Lina Li
- Key Laboratory of Nuclear Analysis Techniques, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Hongbo Fu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
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26
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Affiliation(s)
- Laura Lupi
- Department of Chemistry, The University of Utah, 315 South 1400 East, Salt
Lake City, Utah 84112-0850, United States
| | - Valeria Molinero
- Department of Chemistry, The University of Utah, 315 South 1400 East, Salt
Lake City, Utah 84112-0850, United States
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27
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Tiwari AJ, Morris JR, Vejerano EP, Hochella MF, Marr LC. Oxidation of c60 aerosols by atmospherically relevant levels of o3. Environ Sci Technol 2014; 48:2706-2714. [PMID: 24517376 DOI: 10.1021/es4045693] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Atmospheric processing of carbonaceous nanoparticles (CNPs) may play an important role in determining their fate and environmental impacts. This work investigates the reaction between aerosolized C60 and atmospherically relevant mixing ratios of O3 at differing levels of humidity. Results indicate that C60 is oxidized by O3 and forms a variety of oxygen-containing functional groups on the aerosol surface, including C60O, C60O2, and C60O3. The pseudo-first-order reaction rate between C60 and O3 ranges from 9 × 10(-6) to 2 × 10(-5) s(-1). The reaction is likely to be limited to the aerosol surface. Exposure to O3 increases the oxidative stress exerted by the C60 aerosols as measured by the dichlorofluorescein acellular assay but not by the uric acid, ascorbic acid, glutathione, or dithiothreitol assays. The initial prevalence of C60O and C60O2 as intermediate products is enhanced at higher humidity, as is the surface oxygen content of the aerosols. These results show that C60 can be oxidized when exposed to O3 under ambient conditions, such as those found in environmental, laboratory, and industrial settings.
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Affiliation(s)
- Andrea J Tiwari
- Civil & Environmental Engineering, ‡Chemistry, and §Geosciences, Virginia Tech , Blacksburg, Virginia 24061, United States
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28
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Abstract
Atmospheric aerosols can promote the heterogeneous nucleation of ice, impacting the radiative properties of clouds and Earth's climate. The experimental investigation of heterogeneous freezing of water droplets by carbonaceous particles reveals widespread ice freezing temperatures. It is not known which structural and chemical characteristics of soot account for the variability in ice nucleation efficiency. Here we use molecular dynamics simulations to investigate the nucleation of ice from liquid water in contact with graphitic surfaces. We find that atomically flat carbon surfaces promote heterogeneous nucleation of ice, while molecularly rough surfaces with the same hydrophobicity do not. Graphitic surfaces and other surfaces that promote ice nucleation induce layering in the interfacial water, suggesting that the order imposed by the surface on liquid water may play an important role in the heterogeneous nucleation mechanism. We investigate a large set of graphitic surfaces of various dimensions and radii of curvature and find that variations in nanostructures alone could account for the spread in the freezing temperatures of ice on soot in experiments. We conclude that a characterization of the nanostructure of soot is needed to predict its ice nucleation efficiency.
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Affiliation(s)
- Laura Lupi
- Department of Chemistry, The University of Utah , 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
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Qiu J, Tang CB, Zhu ZJ, Zhou GX, Wang J, Yang Y, Wang GP. XPS and electrochemical impedance spectroscopy studies on effects of the porcelain firing process on surface and corrosion properties of two nickel-chromium dental alloys. J Mater Sci Mater Med 2013; 24:2519-2528. [PMID: 23881280 DOI: 10.1007/s10856-013-5004-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 07/09/2013] [Indexed: 06/02/2023]
Abstract
The aim of this study was to evaluate the effects of a simulated porcelain firing process on the surface, corrosion behavior and cell culture response of two nickel-chromium (Ni-Cr) dental alloys. A Be-free alloy and a Be-containing alloy were tested. Before porcelain firing, as-cast specimens were examined for surface composition using X-ray photoelectron spectroscopy and metallurgical phases using X-ray diffraction. Corrosion behaviors were evaluated using electrochemical impedance spectroscopy. 3T3 fibroblasts were cultured and exposed indirectly to specimens. MTT assays were counted after 3 and 6 days. The cell culture mediums exposed to specimens were analyzed for metal ion release. After porcelain firing, similar specimens were examined for the same properties. In both as-cast and fired conditions, the Be-free Ni-Cr alloy showed significantly more resistance to corrosion than the Be-containing Ni-Cr alloy, which exhibited BeNi phase. After porcelain firing, the corrosion resistance of the Be-free Ni-Cr alloy decreased statistically, corresponding with evident decreases of Cr and Ni oxides on the alloy surface. Also, the alloy's MTT assay decreased significantly corresponding with an obvious increase of Ni-ion release after the firing. For the Be-containing Ni-Cr alloy, the firing process led to increases of surface oxides and metallic Be, while its corrosion resistance and cell culture response were not significantly changed after porcelain firing. The results suggested that the corrosion resistance and biocompatibility of the Be-free Ni-Cr alloy decreased after porcelain firing, whereas the firing process had little effect on the same properties of the Be-containing Ni-Cr alloy.
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Affiliation(s)
- Jing Qiu
- Department of Oral Implantology, Research Institute of Stomatology, College of Stomatology, Nanjing Medical University, Nanjing, 210029, People's Republic of China,
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Affiliation(s)
- Ming-Hui Shang
- Graduate School of Advanced Integration
Science, Chiba University, 1-33 Yayoi-cho,
Inage, Chiba 263-8522, Japan
| | - Takashi Fujikawa
- Graduate School of Advanced Integration
Science, Chiba University, 1-33 Yayoi-cho,
Inage, Chiba 263-8522, Japan
| | - Nobuo Ueno
- Graduate School of Advanced Integration
Science, Chiba University, 1-33 Yayoi-cho,
Inage, Chiba 263-8522, Japan
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