| 1. |
- Alijagic, Andi, 1992-, et al.
(författare)
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A Novel Nanosafety Approach Using Cell Painting, Metabolomics, and Lipidomics Captures the Cellular and Molecular Phenotypes Induced by the Unintentionally Formed Metal-Based (Nano)Particles
- 2023
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Ingår i: Cells. - : MDPI. - 2073-4409. ; 12:2
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Tidskriftsartikel (refereegranskat)abstract
- Additive manufacturing (AM) or industrial 3D printing uses cutting-edge technologies and materials to produce a variety of complex products. However, the effects of the unintentionally emitted AM (nano)particles (AMPs) on human cells following inhalation, require further investigations. The physicochemical characterization of the AMPs, extracted from the filter of a Laser Powder Bed Fusion (L-PBF) 3D printer of iron-based materials, disclosed their complexity, in terms of size, shape, and chemistry. Cell Painting, a high-content screening (HCS) assay, was used to detect the subtle morphological changes elicited by the AMPs at the single cell resolution. The profiling of the cell morphological phenotypes, disclosed prominent concentration-dependent effects on the cytoskeleton, mitochondria, and the membranous structures of the cell. Furthermore, lipidomics confirmed that the AMPs induced the extensive membrane remodeling in the lung epithelial and macrophage co-culture cell model. To further elucidate the biological mechanisms of action, the targeted metabolomics unveiled several inflammation-related metabolites regulating the cell response to the AMP exposure. Overall, the AMP exposure led to the internalization, oxidative stress, cytoskeleton disruption, mitochondrial activation, membrane remodeling, and metabolic reprogramming of the lung epithelial cells and macrophages. We propose the approach of integrating Cell Painting with metabolomics and lipidomics, as an advanced nanosafety methodology, increasing the ability to capture the cellular and molecular phenotypes and the relevant biological mechanisms to the (nano)particle exposure.
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| 2. |
- Alinejadian, Navid, et al.
(författare)
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Electro-deposited nano-Ni/reduced graphene oxide composite film of corrugated surface for high voltammetric sensitivity
- 2023
-
Ingår i: Materials Chemistry and Physics. - : Elsevier BV. - 0254-0584 .- 1879-3312. ; 297, s. 127288-
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Tidskriftsartikel (refereegranskat)abstract
- Reduced graphene oxide (rGO) is an ideal candidate in nanostructured metallic materials to enhance their electrochemical performance. However, few studies exist on the effects of rGO on the crystallographic, physical, and topological properties of co-electrodeposited Ni/rGO nanocomposites. In this study, the morphology and normalized electro-active specific surface (NESS) of a Ni/rGO nanocomposite were correlated with its crystal-lographic properties by varying the applied co-electrodeposition current density (0.01-0.1 A cm(-2)) and rGO concentration (0.5-2 mg mL(-1)). Tuning was done to achieve the best physical and electrochemical properties of the nanocomposite at alkaline (NaOH) conditions in terms of the highest NESS (12.3 x 10(-4)) and electro-active sensitivity (17.3 mu A mM(-1) cm(-2)) possible. The findings of the study show a possible approach to enhance the performance of electro-active components such as electrochemical devices, sensors, and actuators.
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| 3. |
- Alinejadian, Navid, et al.
(författare)
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Importance of the micro-lattice structure of selective laser melting processed Mo/Mo(x)S(x+1) composite : Corrosion studies on the electrochemical performance in aqueous solutions
- 2022
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Ingår i: Materials Today Chemistry. - : Elsevier BV. - 2468-5194. ; 26
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Tidskriftsartikel (refereegranskat)abstract
- Selective laser melting (SLM) based processing of Mo-based samples is challenging due to solidification cracking. We here demonstrate that the addition of 2 wt% MoS2 to the Mo feedstock markedly improves crack mitigation of SLM-processed Mo/MoS2/Mo2S3 composite micro-lattice structures (SLM-Mo/ Mo(x)S(x+1)). Crack inhibition is suggested to be a result of Mo2S3 formation, decreased lattice strain (0.04 4%), and a decrease in accumulated residual stresses. The increased values of polarization resistance from 42.3 and 19.2 kU cm2 to 437 and 78.2 kU cm2, respectively verified the hindering effect of the composition on stress corrosion cracking (SCC) and surface oxidation cracking. However, an increased corrosion current density, from 1.22 to 10.2 mA/cm2, and cathodic Tafel constant, from 175 to 260.5 mV, confirmed the decreased polarization resistance and occurrence of different types of corrosion such as SCC and pitting. The strategy to add 2 wt% MoS2 to the Mo feedstock enables the fabrication of hightemperature micro-lattice structure components with improved corrosion resistance properties applicable in e.g., electronic, power semiconductor heat sinks, offshore-, aerospace-, defense-, or particularly novel sodium-ion energy storage applications.
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| 4. |
- Alinejadian, Navid, et al.
(författare)
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Progress in additive manufacturing of MoS2-based structures for energy storage applications - A review
- 2022
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Ingår i: Materials Science in Semiconductor Processing. - : Elsevier BV. - 1369-8001 .- 1873-4081. ; 139
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Forskningsöversikt (refereegranskat)abstract
- Investigation of next-generation manufacturing methods for the processing of functional materials and offering products with improved performance/functionalities has always been a challenge in terms of energy efficiency, cost-effectiveness, and eco-friendliness. Additive manufacturing (AM) attributes to rapid prototyping techniques that provide new opportunities to test new concepts and design complex 3D structures from metals, ceramics, and composites. Moreover, as a well-known transition metal dichalcogenide, Molybdenum disulfide (MoS2) is a two-dimensional (2D) material with outstanding electrochemical, physical, and mechanical properties that make it a potential candidate for energy storage electrodes via intercalation of different H+, Li+, Na+, and K+ cations. In this review, we discuss the existing conventional MoS2-processing methodologies and compare them with the novel additive manufacturing processes (especially laser-based powder bed fusion). The authors are convinced that the processing of prominent MoS2-based functional structures by the novel additive manufacturing processes can provide complex structures for different electrochemical applications, particularly for energy conversion/ storage systems.
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| 5. |
- Alinejadian, Navid, et al.
(författare)
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SLM-processed MoS2/Mo2S3 nanocomposite for energy conversion/storage applications
- 2022
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Ingår i: Scientific Reports. - : Nature Research. - 2045-2322. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- MoS2-based nanocomposites have been widely processed by a variety of conventional and 3D printing techniques. In this study, selective laser melting (SLM) has for the first time successfully been employed to tune the crystallographic structure of bulk MoS2 to a 2H/1T phase and to distribute Mo2S3 nanoparticles in-situ in MoS2/Mo2S3 nanocomposites used in electrochemical energy conversion/storage systems (EECSS). The remarkable results promote further research on and elucidate the applicability of laser-based powder bed processing of 2D nanomaterials for a wide range of functional structures within, e.g., EECSS, aerospace, and possibly high-temperature solid-state EECSS even in space.
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| 6. |
- Atapour, Masoud, et al.
(författare)
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Corrosion and metal release investigations of selective laser melted 316L stainless steel in a synthetic physiological fluid containing proteins and in diluted hydrochloric acid
- 2020
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Ingår i: Electrochimica Acta. - : Elsevier BV. - 0013-4686 .- 1873-3859. ; 354
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Tidskriftsartikel (refereegranskat)abstract
- The corrosion and metal release characteristics of additively manufactured stainless steels are key factors for their applicability in biomedical applications. The effect of building direction on the microstructure, corrosion behavior and metal release of selective laser melted (SLM) AISI 316L stainless steel were therefore investigated in a protein-rich synthetic body fluid (PBS+BSA, pH 7.3) and in diluted hydrochloric acid (HCl, pH 1.5). A multi-analytical approach was applied to characterize SLM 316L surfaces printed in different building directions (denoted XY and XZ) and a post heat treated SLM surface (XZ-HT) compared with wrought surfaces. All SLM specimens revealed an austenitic microstructure without any amounts of delta-ferrite and without large-angled grain boundaries in contrast to the wrought 316L surface. The building direction strongly affected the grain size distribution due to the temperature gradients in the melt pools. The SLM 316L specimens released initially slightly less Fe, Cr and Ni compared with the wrought 316L specimen. Slightly less metal was released from the heat treated SLM specimen (XZ-HT) specimen compared to the other SLM specimens. Relatively high amounts of released Cr were observed in PBS+BSA, most probably attributed to protein-bound Cr, whereas substantially more Ni was released in HCl compared to PBS+BSA due to pitting corrosion and a reduced surface oxide thickness. The surface oxide composition of as-printed SLM specimens was strongly dependent on the building direction and the post heat treatment, whereas no differences were observed after abrasion either among the SLM specimens or compared with the wrought 316L specimen. Cr became in all cases enriched within the outermost surface oxide in PBS+BSA and strongly enriched in the HCl solution, coupled to a strongly reduced amount of released metals with time. The heat treated SLM specimen (XZ-HT) gained a superior charge transfer resistance, the lowest passive current density, and the highest OCP value among all specimens. In HCl, the SLM specimens showed a lower pitting susceptibility compared to the wrought specimens. No pitting was observed in PBS+BSA. No differences in corrosion or metal release characteristics were observed related to the building direction of abraded SLM specimens.
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| 7. |
- Atapour, Masoud, et al.
(författare)
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Corrosion of Binder Jetting Additively Manufactured 316L Stainless Steel of Different Surface Finish
- 2020
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Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 0013-4651 .- 1945-7111. ; 167:13
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Tidskriftsartikel (refereegranskat)abstract
- One technique of additive manufacturing is the binder-jetting technique that has the advantages of low costs, printing at room temperature and in air, and no need of a support structure. The aim of this study was to investigate the corrosion behavior of printed 316L surfaces with and without different post surface treatments of blasting and superfinishing. Comparative studies were performed on abraded wrought 316L. Surface topography, porosity, surface oxide composition, and electrochemical characteristics, including pitting corrosion, were investigated at room temperature as a function of post surface treatments in diluted hydrochloric acid at pH 1.5. The blasting and superfinishing treatment significantly reduced the surface roughness and level of surface porosity. Blasting detrimentally affected on the pitting corrosion resistance. The superfinishing process induced an enrichment of chromium in the surface oxide and improved the pitting corrosion resistance. All surfaces revealed slightly reduced susceptibility to pit initiation and metastable pitting as compared to wrought 316L, possibly explained by the absence of inclusions. Once pitting propagation was induced, repassivation was hindered for all surfaces compared with the wrought surface. The pitting corrosion resistance of the as-superfinished 316L was improved compared with wrought 316L.
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| 8. |
- Atapour, Masoud, et al.
(författare)
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Metal release from stainless steel 316L in whey protein - And simulated milk solutions under static and stirring conditions
- 2019
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Ingår i: Food Control. - : ELSEVIER SCI LTD. - 0956-7135 .- 1873-7129. ; 101, s. 163-172
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Tidskriftsartikel (refereegranskat)abstract
- Stainless steel is an important transport and processing contact material for bovine milk and dairy products. Release (migration) of metals, ions, complexes or wear debris/particles, and metal-induced protein aggregation in such environments are hence important to consider both from a corrosion and food safety perspective. This study aims on investigating the release of iron (Fe), chromium (Cr), and nickel (Ni) from AISI 316L stainless steel in contact with whey protein solutions relevant for protein drinks, and on how the whey proteins are influenced by stirring with a magnetic stir bar and metal release. Mechanistic insight is gained by parallel investigations of metal release from two reference non-protein containing solutions, a metal-complexing (citrate-containing) simulated milk solution (SMS) and a low complexing phosphate buffered saline solution (PBS). All immersion exposures were conducted at pH 6.8 for 0.5, 4, 24 and 48 hat room temperature at static and stirring conditions. All solutions and samples were investigated using different chemical, spectroscopic, microscopic, and electrochemical methods. Significantly higher amounts of Fe, Cr, and Ni were released into the whey protein solution (80 g/L) as compared to SMS and PBS. Strong enrichment of Cr in the surface oxide and reduction of the surface oxide thickness were associated with a higher amount of Ni release in the metal-complexing solutions (SMS and whey protein) compared with PBS. Stirring conditions resulted in higher amounts of metal release, enrichment of Cr in the surface oxide, and clear signs of wear of the 316L surface in all solutions compared to static conditions. The wear mechanism in the whey protein solution was different as compared to corresponding processes in SMS and PBS, involving an etching-like process and larger-sized wear debris. Electrochemical measurements at static conditions confirmed observed differences between the solutions, with the lowest corrosion resistance observed for coupons exposed in the whey protein solution, followed by SMS and PBS. Released metals in solution from the 316L coupons in contact with the whey protein solution resulted in enhanced rates of protein aggregation and precipitation of protein aggregates from solution. Further studies should be made to investigate other relevant test conditions and assess toxicological risks.
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| 9. |
- Atapour, Masoud, et al.
(författare)
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Stainless steel in simulated milk and whey protein solutions - Influence of grade on corrosion and metal release
- 2020
-
Ingår i: Electrochimica Acta. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0013-4686 .- 1873-3859. ; 331
-
Tidskriftsartikel (refereegranskat)abstract
- Reactions at the biointerfaces between stainless steel and protein-rich dairy products, which contain whey proteins, are important to consider in terms of food safety and material grade selection. Changes in corrosion behavior, metal release, and surface composition of austenitic (AISI 316 L), ferritic (AISI 430), and lean duplex (LDX 2101) stainless steels in simulated milk (SMS) and whey protein solution were investigated. The amount of released metals and the corrosion susceptibility increased according to 2101 < 316 L < 430. All grades revealed low corrosion rates in the whey protein solution without any sign of active/metastable corrosion. Pitting corrosion was evident for 430 in SMS. The total amount of released metals (iron, chromium, and nickel) was significantly higher in whey protein solution compared with SMS. This suggests the metal release process to be mainly governed by complexation reactions. Nickel was preferentially released compared to its bulk composition fraction for both 316 L and 2101 in the highly complexing SMS. Reduced metal release rates with time correlated with the enrichment of chromium in the surface oxide. The extent of metal release was for all metals substantially lower than release limits of metals stipulated in health regulations related to the use of alloys and metals in food-related environments.
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| 10. |
- Bahar, Babak, et al.
(författare)
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Corrosion-induced copper release from rain gutters
- 2008
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Ingår i: Metall (Berlin. 1947). - 0026-0746. ; 62:3, s. 129-135
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Tidskriftsartikel (refereegranskat)abstract
- While runoff rates from copper roofs have been extensively studied during the last years, corresponding studies from copper rain gutters have been missing. A laboratory investigation has been undertaken to examine the influence of important runoff water parameters on the copper runoff from rain gutters. At a given rainfall quantity, the release rate of copper increases with decreasing runoff water intensity and decreasing degree of gutter inclination, and with increasing runoff acidity and increasing Cu2+-ion concentration in the runoff water. A comparison of the predicted long-term copper release from the gutter-system compared to the roof on a real building suggests that less than 5% of the total copper runoff originates from the gutter. However, single rain events may result in higher release rates, especially during the initial rain portion.
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| 11. |
- Bender, R., et al.
(författare)
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Corrosion challenges towards a sustainable society
- 2022
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Ingår i: Materials and corrosion - Werkstoffe und Korrosion. - : Wiley. - 0947-5117 .- 1521-4176. ; 73:11, s. 1730-1751
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Tidskriftsartikel (refereegranskat)abstract
- A global transition towards more sustainable, affordable and reliable energy systems is being stimulated by the Paris Agreement and the United Nation's 2030 Agenda for Sustainable Development. This poses a challenge for the corrosion industry, as building climate-resilient energy systems and infrastructures brings with it a long-term direction, so as a result the long-term behaviour of structural materials (mainly metals and alloys) becomes a major prospect. With this in mind “Corrosion Challenges Towards a Sustainable Society” presents a series of cases showing the importance of corrosion protection of metals and alloys in the development of energy production to further understand the science of corrosion, and bring the need for research and the consequences of corrosion into public and political focus. This includes emphasis on the limitation of greenhouse gas emissions, on the lifetime of infrastructures, implants, cultural heritage artefacts, and a variety of other topics.
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| 12. |
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| 13. |
- Blomberg, Eva, 1961-, et al.
(författare)
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Weathering and Antimicrobial Properties of Laminate and Powder Coatings Containing Silver Phosphate Glass Used as High-Touch Surfaces
- 2022
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Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 14:12, s. 7102-
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Tidskriftsartikel (refereegranskat)abstract
- Increasing the use of hygienic high-touch surfaces with antimicrobial properties in health care and public spaces is one way to hinder the spread of bacteria and infections. This study investigates the antimicrobial efficacy and surface reactivity of commercial laminate and powder coated surfaces treated with silver-doped phosphate glass as antimicrobial additive towards two model bacterial strains, Escherichia coli and Bacillus subtilis, in relation to surface weathering and repeated cleaning. High-touch conditions in indoor environments were simulated by different extents of pre-weathering (repeated daily cycles in relative humidity at constant temperature) and simplified fingerprint contact by depositing small droplets of artificial sweat. The results elucidate that the antimicrobial efficacy was highly bacteria dependent (Gram-positive or Gram-negative), not hampered by differences in surface weathering but influenced by the amount of silver-doped additive. No detectable amounts of silver were observed at the top surfaces, though silver was released into artificial sweat in concentrations a thousand times lower than regulatory threshold values stipulated for materials and polymers in food contact. Surface cleaning with an oxidizing chemical agent was more efficient in killing bacteria compared with an agent composed of biologically degradable constituents. Cleaning with the oxidizing agent resulted further in increased wettability and presence of residues on the surfaces, effects that were beneficial from an antimicrobial efficacy perspective.
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| 14. |
- Cappellini, Francesca, et al.
(författare)
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Dry Generation of CeO2 Nanoparticles and Deposition onto a Co-Culture of A549 and THP-1 Cells in Air-Liquid Interface-Dosimetry Considerations and Comparison to Submerged Exposure
- 2020
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Ingår i: Nanomaterials. - : MDPI AG. - 2079-4991. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- Relevant in vitro assays that can simulate exposure to nanoparticles (NPs) via inhalation are urgently needed. Presently, the most common method employed is to expose lung cells under submerged conditions, but the cellular responses to NPs under such conditions might differ from those observed at the more physiological air-liquid interface (ALI). The aim of this study was to investigate the cytotoxic and inflammatory potential of CeO2 NPs (NM-212) in a co-culture of A549 lung epithelial cells and differentiated THP-1 cells in both ALI and submerged conditions. Cellular dose was examined quantitatively using inductively coupled plasma mass spectrometry (ICP-MS). The role of serum and LPS-priming for IL-1 beta release was further tested in THP-1 cells in submerged exposure. An aerosol of CeO2 NPs was generated by using the PreciseInhale (R) system, and NPs were deposited on the co-culture using XposeALI (R). No or minor cytotoxicity and no increased release of inflammatory cytokines (IL-1 beta, IL-6, TNF alpha, MCP-1) were observed after exposure of the co-culture in ALI (max 5 mu g/cm(2)) or submerged (max 22 mu g/cm(2)) conditions. In contrast, CeO2 NPs cause clear IL-1 beta release in monocultures of macrophage-like THP-1, independent of the presence of serum and LPS-priming. This study demonstrates a useful approach for comparing effects at various in-vitro conditions.
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| 15. |
- Cappellini, Francesca, et al.
(författare)
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Mechanistic insight into reactivity and (geno)toxicity of well-characterized nanoparticles of cobalt metal and oxides
- 2018
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Ingår i: Nanotoxicology. - : Taylor & Francis. - 1743-5390 .- 1743-5404. ; 12:6, s. 602-620
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Tidskriftsartikel (refereegranskat)abstract
- An increasing use of cobalt (Co)-based nanoparticles (NPs) in different applications and exposures at occupational settings triggers the need for toxicity assessment. Improved understanding regarding the physiochemical characteristics of Co metal NPs and different oxides in combination with assessment of toxicity and mechanisms may facilitate decisions for grouping during risk assessment. The aim of this study was to gain mechanistic insights in the correlation between NP reactivity and toxicity of three different Co-based NPs (Co, CoO, and Co3O4) by using various tools for characterization, traditional toxicity assays, as well as six reporter cell lines (ToxTracker) for rapid detection of signaling pathways of relevance for carcinogenicity. The results showed cellular uptake of all NPs in lung cells and induction of DNA strand breaks and oxidative damage (comet assay) by Co and CoO NPs. In-depth studies on the ROS generation showed high reactivity of Co, lower for CoO, and no reactivity of Co3O4 NPs. The reactivity depended on the corrosion and transformation/dissolution properties of the particles and the media highlighting the role of the surface oxide and metal speciation as also confirmed by in silico modeling. By using ToxTracker, Co NPs were shown to be highly cytotoxic and induced reporters related to oxidative stress (Nrf2 signaling) and DNA strand breaks. Similar effects were observed for CoO NPs but at higher concentrations, whereas the Co3O4 NPs were inactive at all concentrations tested. In conclusion, our study suggests that Co and CoO NPs, but not Co3O4, may be grouped together for risk assessment.
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| 16. |
- Chang, Tingru, et al.
(författare)
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A mechanistic study of stratified patina evolution on Sn-bronze in chloride-rich atmospheres
- 2020
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Ingår i: Corrosion Science. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0010-938X .- 1879-0496. ; 166
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Tidskriftsartikel (refereegranskat)abstract
- The complex stratified patina formed on Sn-bronze in chloride-rich atmospheres has been explored through long-term field exposures and short-term laboratory investigations using a multi-analytical approach. The stratified patina is composed of Cu2O- and Cu-2(OH)(3)Cl-rich sublayers intercalated by Sn-oxides, mainly SnO2. The stratification is triggered by events of high chloride deposition, resulting in repeated dissolution and solidification of sublayers, whereby redox reactions between the intermediate products of Sn- and Cu-chlorides play a crucial role. Sn-induced patina stratification is a major reason for enhanced patina flaking on Sn-bronze and its accelerated corrosion rate compared to Cu metal in marine environments.
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| 17. |
- Chang, Tingru, et al.
(författare)
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A novel methodology to study antimicrobial properties of high-touch surfaces used for indoor hygiene applications-A study on Cu metal
- 2021
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 16:2
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Tidskriftsartikel (refereegranskat)abstract
- Metal-based high-touch surfaces used for indoor applications such as doorknobs, light switches, handles and desks need to remain their antimicrobial properties even when tarnished or degraded. A novel laboratory methodology of relevance for indoor atmospheric conditions and fingerprint contact has therefore been elaborated for combined studies of both tarnishing/corrosion and antimicrobial properties of such high-touch surfaces. Cu metal was used as a benchmark material. The protocol includes pre-tarnishing/corrosion of the high touch surface for different time periods in a climatic chamber at repeated dry/wet conditions and artificial sweat deposition followed by the introduction of bacteria onto the surfaces via artificial sweat droplets. This methodology provides a more realistic and reproducible approach compared with other reported procedures to determine the antimicrobial efficiency of high-touch surfaces. It provides further a possibility to link the antimicrobial characteristics to physical and chemical properties such as surface composition, chemical reactivity, tarnishing/corrosion, surface roughness and surface wettability. The results elucidate that bacteria interactions as well as differences in extent of tarnishing can alter the physical properties (e.g. surface wettability, surface roughness) as well as the extent of metal release. The results clearly elucidate the importance to consider changes in chemical and physical properties of indoor hygiene surfaces when assessing their antimicrobial properties.
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| 18. |
- Chang, Tingru, et al.
(författare)
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Analysis of historic copper patinas. Influence of inclusions on patina uniformity
- 2017
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Ingår i: Materials. - : MDPI AG. - 1996-1944. ; 10:3
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Tidskriftsartikel (refereegranskat)abstract
- The morphology and elemental composition of cross sections of eight historic copper materials have been explored. The materials were taken from copper roofs installed in different middle and northern European environments from the 16th to the 19th century. All copper substrates contain inclusions of varying size, number and composition, reflecting different copper ores and production methods. The largest inclusions have a size of up to 40 μm, with most inclusions in the size ranging between 2 and 10 μm. The most common element in the inclusions is O, followed by Pb, Sb and As. Minor elements include Ni, Sn and Fe. All historic patinas exhibit quite fragmentized bilayer structures, with a thin inner layer of cuprite (Cu2O) and a thicker outer one consisting mainly of brochantite (Cu4SO4(OH)6). The extent of patina fragmentation seems to depend on the size of the inclusions, rather than on their number and elemental composition. The larger inclusions are electrochemically nobler than the surrounding copper matrix. This creates micro-galvanic effects resulting both in a profound influence on the homogeneity and morphology of historic copper patinas and in a significantly increased ratio of the thicknesses of the brochantite and cuprite layers. The results suggest that copper patinas formed during different centuries exhibit variations in uniformity and corrosion protection ability.
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| 19. |
- Chang, Tingru
(författare)
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Atmospheric corrosion of copper and copper-based alloys in architecture : from native surface oxides to fully developed patinas
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Copper and copper-based alloys are commonly used in both ancient and modern architecture. This requires an in-depth fundamental and applied understanding on their atmospheric corrosion behavior at different climatic, environmental and pollutant levels and how these parameters influence e.g. corrosion initiation, patina characteristics, aesthetic appearances, corrosion rates, and runoff rates. This doctoral thesis elucidates the role of native surface oxides on the corrosion performance, corrosion initiation, formation and evolution of corrosion products from hours to months, years and even centuries, to diffuse dispersion of metals from Cu metal/Cu alloy surfaces focusing on the roles of alloying elements, microstructure, and deposition of chlorides. In-depth investigations have been performed at both laboratory and field conditions on commercial Cu metal and copper-based alloys of a golden alloy (Cu5Zn5Al1Sn) and Sn-bronzes (Cu4Sn, Cu6Sn). Patina characteristics and relations to the presence of microstructural inclusions have in addition been investigated for historic patinas of Cu metal roofing of different age and origin, highlighted with data for a 400 years old Cu patina exposed at urban conditions.A multi-analytical approach comprising microscopic, spectroscopic and electrochemical methods was employed for in-depth investigations of surface characteristics and bulk properties. Electron backscattered diffraction (EBSD) was utilized to characterize the microstructure. Auger electron spectroscopy (scanning-AES), X-ray photoelectron spectroscopy (XPS), glow discharge optical emission spectroscopy (GDOES) were employed for surface chemical compositional analysis, and atomic absorption spectroscopy (AAS) to assess the amount of metal release from the patinas. Cathodic reduction (CR) and electrochemical impedance spectroscopy (EIS) were used to assess the amount and corrosion resistance of corrosion products formed at laboratory conditions. Confocal Raman micro-spectroscopy (CRM), infrared reflection absorption spectroscopy (IRAS) and grazing incidence X-ray diffraction (GIXRD) were used to identify the phases of corrosion products. Colorimetry was used to assess surface appearances.Cu5Zn5Al1Sn and Cu4Sn/Cu6Sn exhibit favorable bulk properties with respect to corrosion in terms of smaller grain size compared with Cu metal and show non-significant surface compositional variations. The presence of multi-component native oxides predominantly composed of Cu2O enriched with Sn-oxides on Cu4Sn/Cu6Sn, and with ZnO, SnO2 and Al2O3 on Cu5Zn5Al1Sn, improves the barrier properties of the native surface oxides and the overall corrosion resistance of Cu4Sn/Cu6Sn and Cu5Zn5Al1Sn. The formation of Zn/Al/Sn-containing corrosion products (e.g. Zn5(CO3)2(OH)6 and Zn6Al2(OH)16CO3·4H2O) significantly reduces the corrosion rate of Cu5Zn5Al1Sn in chloride-rich environments. Alloying with Sn reduces the corrosion rate of Sn-bronze at urban environments of low chloride levels but results in enhanced corrosion rates at chloride-rich marine conditions.A clear dual-layer structure patina was observed for centuries-old naturally patinated copper metal with an origin from the roof of Queen Anne's Summer Palace in Prague, the Czech Republic. The patina comprises an inner sub-layer of Cu2O and an outer sub-layer of Cu4SO4(OH)6/Cu3SO4(OH)4. Abundant relatively noble inclusions (mainly rosiaite (PbSb2O6)) were observed and incorporated in both the copper matrix and the patina. The largest inclusions of higher nobility than the surrounding material create significant micro-galvanic effects that result in a fragmentized patina and large thickness ratios between the Cu4SO4(OH)6/Cu3SO4(OH)4 and the Cu2O sub-layer, investigated via a statistical analysis of inclusions and patina characteristics of eight different historic urban copper patinas.
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| 20. |
- Chang, Tingru, et al.
(författare)
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Effect of blue light illumination on atmospheric corrosion and bacterial adhesion on copper
- 2024
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Ingår i: Corrosion Science. - : Elsevier BV. - 0010-938X .- 1879-0496. ; 230
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Tidskriftsartikel (refereegranskat)abstract
- The effect of blue light on atmospheric corrosion of Cu and on the antimicrobial properties was explored upon exposure mimicking the condition of hygienic surface disinfection. The results show that blue light illumination enhanced the formation of Cu2O, resulting in a slightly increased corrosion resistance of Cu without pre-deposited NaCl, whereas the enhanced formation of Cu2O, CuCl and/or Cu(OH)3Cl on copper with pre-deposited NaCl caused concomitant corrosion product flaking and a reduced corrosion resistance. The blue light induced enhancement of Cu corrosion led to increased surface roughness and more pronounced integration of bacteria within the corrosion products.
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| 21. |
- Chang, Tingru, et al.
(författare)
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Effects of interactions between natural organic matter and aquatic organism degradation products on the transformation and dissolution of cobalt and nickel-based nanoparticles in synthetic freshwater
- 2023
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 445, s. 130586-130586
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Tidskriftsartikel (refereegranskat)abstract
- Expanding applications and production of engineered nanoparticles lead to an increased risk for their environmental dispersion. Systematic knowledge of surface transformation and dissolution of nanoparticles is essential for risk assessment and regulation establishment. Such aspects of Co- and Ni-based nanoparticles including metals, oxides, and solution combustion synthesized metal nanoparticles (metal cores with carbon shells) were investigated upon environmental interaction with organic matter, simulated by natural organic matter (NOM) and degradation products from zooplankton and algae (eco-corona biomolecules, EC) in freshwater (FW). The presence of NOM and EC in FW results in negative surface charges of the nanoparticles reduces the extent of nanoparticles agglomeration, and increases concentration, mainly due to the surface adsorption of carboxylate groups of the organic matter. The dissolution of the Co-based nanoparticles was for all conditions (FW, FW with NOM or EC) higher than the Ni-based, except for Co3O4 being nearly non-soluble. The surface transformation and dissolution of nanoparticles are highly exposure and time-dependent, and surface- and environment specific. Therefore, no general correlation was observed between dissolution and, particle types, surface conditions, or EC/NOM adsorption. This underlines the importance of thorough investigations of nanoparticles adsorption/desorption, degradation, and exposure scenarios for developing regulatory relevant protocols and guidelines.
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| 22. |
- Chang, Tingru, et al.
(författare)
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High-Resolution Microscopical Studies of Contact Killing Mechanisms on Copper-Based Surfaces
- 2021
-
Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 13:41, s. 49402-49413
-
Tidskriftsartikel (refereegranskat)abstract
- The mechanisms of bacterial contact killing induced by Cu surfaces were explored through high-resolution studies based on combinations of the focused ion beam (FIB), scanning transmission electron microscopy (STEM), high-resolution TEM, and nanoscale Fourier transform infrared spectroscopy (nano-FTIR) microscopy of individual bacterial cells of Gram-positive Bacillus subtilis in direct contact with Cu metal and Cu5Zn5Al1Sn surfaces after high-touch corrosion conditions. This approach permitted subcellular information to be extracted from the bioinorganic interface between a single bacterium and Cu/Cu5Zn5Al1Sn surfaces after complete contact killing. Early stages of interaction between individual bacteria and the metal/alloy surfaces include cell leakage of extracellular polymeric substances (EPSs) from the bacterium and changes in the metal/alloy surface composition upon adherence of bacteria. Three key observations responsible for Cu-induced contact killing include cell membrane damage, formation of nanosized copper-containing particles within the bacteria cell, and intracellular copper redox reactions. Direct evidence of cell membrane damage was observed upon contact with both Cu metal and Cu5Zn5Al1Sn surfaces. Cell membrane damage permits copper to enter into the cell interior through two possible routes, as small fragmentized Cu2O particles from the corrosion product layer and/or as released copper ions. This results in the presence of intracellular copper oxide nanoparticles inside the cell. The nanosized particles consist primarily of CuO with smaller amounts of Cu2O. The existence of two oxidation states of copper suggests that intracellular redox reactions play an important role. The nanoparticle formation can be regarded as a detoxification process of copper, which immobilizes copper ions via transformation processes within the bacteria into poorly soluble or even insoluble nanosized Cu structures. Similarly, the formation of primarily Cu(II) oxide nanoparticles could be a possible way for the bacteria to deactivate the toxic effects induced by copper ions via conversion of Cu(I) to Cu(II).
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| 23. |
- Chang, Tingru, et al.
(författare)
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The golden alloy Cu5Zn5Al1Sn : Patina evolution in chloride-containing atmospheres
- 2018
-
Ingår i: Corrosion Science. - : Elsevier. - 0010-938X .- 1879-0496. ; 133, s. 190-203
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Tidskriftsartikel (refereegranskat)abstract
- The influence of chloride deposition on the formation, evolution and barrier properties of the patina formed on CuSZn5Al1Sn used for architectural cladding is explored via long-term marine field exposures and laboratory investigations. The presence of Cu2O, ZnO, Al2O3 and SnO2 within the inner part of the patina and intercalation of SnO2, Zn-5(CO3)(2)(OH)(6), Zn6Al2(OH)(16)CO3 center dot 4H(2)O, Zn-5(OH)(8)Cl-2 center dot H2O within its outer part, predominantly composed of Cu-2(OH)(3)Cl, significantly reduce the chloride-induced corrosion compared with Cu metal. The intercalation of zinc-rich corrosion products within the patina and not at the top-surface explain their marginal influence on the runoff process that mainly occurs at the outmost surface.
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| 24. |
- Chang, Tingru, et al.
(författare)
-
The interplay between atmospheric corrosion and antimicrobial efficiency of Cu and Cu5Zn5Al1Sn during simulated high-touch conditions
- 2021
-
Ingår i: Corrosion Science. - : Elsevier BV. - 0010-938X .- 1879-0496. ; 185
-
Tidskriftsartikel (refereegranskat)abstract
- The interplay between atmospheric corrosion and antimicrobial efficiency of bare Cu and Cu5Zn5Al1Sn was studied upon exposures simulating high-touch surface conditions. The survival of the bacteria Bacillus subtilis during surface contact with Cu and Cu5Zn5Al1Sn was examined under different degrees of surface oxidation, tarnishing, wettability and copper ion release. Depending on surface conditions complete bacteria inhibition was obtained within 4 min on Cu and within 6-10 min on Cu5Zn5Al1Sn. The antibacterial efficiency increases slightly with copper release rate and is governed by complex interactions between the corroded metal surface, bacteria and extracellular polymeric substances produced by the bacteria.
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| 25. |
- Chang, Tingru, et al.
(författare)
-
The role of Sn on the long-term atmospheric corrosion of binary Cu-Sn bronze alloys in architecture
- 2019
-
Ingår i: Corrosion Science. - : Elsevier Ltd. - 0010-938X .- 1879-0496. ; 149, s. 54-67
-
Tidskriftsartikel (refereegranskat)abstract
- The role of Sn on the atmospheric corrosion performance of binary Cu-Sn bronze alloys (4–6 wt.% Sn) compared with Cu metal used in outdoor architecture is elucidated in terms of microstructure, native surface oxide composition, patina evolution, corrosion rates, appearance and metal release. Results are presented for non-exposed surfaces and surfaces exposed at different urban and marine sites in Europe up to 5 years and based on multi-analytical findings from microscopic, spectroscopic, electrochemical and chemical investigations. Alloying influenced the corrosion, aesthetic appearance and patina evolution, differently for urban and marine sites, whereas no effects were observed on the release pattern. © 2019 The Authors
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| 26. |
- Chang, Tingru, et al.
(författare)
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Understanding the Barrier Layer Formed via Adding BTAH in Copper Film Electrodeposition
- 2019
-
Ingår i: Journal of the Electrochemical Society. - : ELECTROCHEMICAL SOC INC. - 0013-4651 .- 1945-7111. ; 166:2, s. D10-D20
-
Tidskriftsartikel (refereegranskat)abstract
- The influence of surface adsorption of benzotriazole (BTAH) and of chloride ions (Cl-) on the kinetics of copper electrodeposition/dissolution in copper sulfate solutions and on copper deposit characteristics have been investigated using electrochemical quartz crystal microbalance (EQCM) combined with cyclic voltammetry (CV). The addition of BTAH alone increases the overpotential of copper deposition, whereas a Cu(I)BTA complex forms at potentials higher than 0.08 V (vs. SCE) accompanied with the occurrence of copper anodic dissolution. With simultaneous addition of BTAH and Cl-, surface adsorption of Cl- competes with that of BTAH during the initial stage of copper nucleation. Different cuprous reaction intermediates form in the examined potential range -0.4 to 0.3 V (vs. SCE), which partly eliminate the favorable effect of BTAH on the deposited copper. A BTAH-containing adsorbed layer formed on the matte side of electrodeposited copper film in the presence of BTAH with or without Cl-, exhibiting a barrier surface property and an improved corrosion resistance compared with the copper film electrodeposited in the electrolyte without addition of BTAH.
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| 27. |
- Chico, B., et al.
(författare)
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Analysis of historic copper patinas 2 : Characterization of 400 year old patina from Royal Summer Palace in Prague
- 2017
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Ingår i: EUROCORR 2017 - The Annual Congress of the European Federation of Corrosion, 20th International Corrosion Congress and Process Safety Congress 2017. - : Asociace koroznich inzenyru z.s.- AKI - Czech Association of Corrosion Engineers.
-
Konferensbidrag (refereegranskat)abstract
- This paper presents an in-depth characterisation study of the patina formed on a copper tile taken from the roof of Queen Anne's Summer Palace in Prague after close to 400 years of exposure to the action of the atmosphere. A wide variety of techniques have been performed, including metallographic and chemical analysis (electrogravimetry, AAS, XRF) of the copper matrix, and spectroscopic and microscopic investigations (GIXRD, TEM/EDS and SEM/EDS) to determine the composition and structure of the patina. The major conclusions of the study are: (a) the base copper contains abundant inclusions mainly of rosiaite (PbSb2O6); (b) the patina is formed by an inner sublayer of cuprite (Cu2O) and an outer sublayer of brochantite [Cu4SO4(OH)6] and antlerite [Cu3SO4(OH)4] and traces of azurite [Cu3(CO3)2(OH)2]; and (c) the brochantite/antlerite crystals are randomly doped with Fe and C.
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| 28. |
- Di Bucchianico, Sebastiano, et al.
(författare)
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Calcium-dependent cyto- and genotoxicity of nickel metal and nickel oxide nanoparticles in human lung cells
- 2018
-
Ingår i: Particle and Fibre Toxicology. - : BMC. - 1743-8977. ; 15
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Genotoxicity is an important toxicological endpoint due to the link to diseases such as cancer. Therefore, an increased understanding regarding genotoxicity and underlying mechanisms is needed for assessing the risk with exposure to nanoparticles (NPs). The aim of this study was to perform an in-depth investigation regarding the genotoxicity of well-characterized Ni and NiO NPs in human bronchial epithelial BEAS-2B cells and to discern possible mechanisms. Comparisons were made with NiCl2 in order to elucidate effects of ionic Ni. Methods: BEAS-2B cells were exposed to Ni and NiO NPs, as well as NiCl2, and uptake and cellular dose were investigated by transmission electron microscopy (TEM) and inductively coupled plasma mass spectrometry (ICP-MS). The NPs were characterized in terms of surface composition (X-ray photoelectron spectroscopy), agglomeration (photon cross correlation spectroscopy) and nickel release in cell medium (ICP-MS). Cell death (necrosis/apoptosis) was investigated by Annexin VFITC/PI staining and genotoxicity by cytokinesis-block micronucleus (cytome) assay (OECD 487), chromosomal aberration (OECD 473) and comet assay. The involvement of intracellular reactive oxygen species (ROS) and calcium was explored using the fluorescent probes, DCFH-DA and Fluo-4. Results: NPs were efficiently taken up by the BEAS-2B cells. In contrast, no or minor uptake was observed for ionic Ni from NiCl2. Despite differences in uptake, all exposures (NiO, Ni NPs and NiCl2) caused chromosomal damage. Furthermore, NiO NPs were most potent in causing DNA strand breaks and generating intracellular ROS. An increase in intracellular calcium was observed and modulation of intracellular calcium by using inhibitors and chelators clearly prevented the chromosomal damage. Chelation of iron also protected against induced damage, particularly for NiO and NiCl2. Conclusions: This study has revealed chromosomal damage by Ni and NiO NPs as well as Ni ionic species and provides novel evidence for a calcium-dependent mechanism of cyto- and genotoxicity.
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| 29. |
- Ekvall, Mikael T., et al.
(författare)
-
Adsorption of bio-organic eco-corona molecules reduces the toxic response to metallic nanoparticles in Daphnia magna
- 2021
-
Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- As the use of engineered nanomaterials increases, so does the risk of them spreading to natural ecosystems. Hitherto, knowledge regarding the toxic properties of nanoparticles (NP's) and their potential interactions with natural bio-organic molecules adsorbed to them, and thereby forming surface coronas, is limited. However, we show here that the toxic effect of NPs of tungsten carbide cobalt (WC-Co) and cobalt (Co) on the crustacean Daphnia magna is postponed in the presence of natural biological degradation products (eco-corona biomolecules). For Daphnia exposed to WC-Co NPs the survival time increased with 20-25% and for Co NPs with 30-47% after mixing the particles with a solution of eco-corona biomolecules before exposure. This suggests that an eco-corona, composed of biomolecules always present in natural ecosystems, reduces the toxic potency of both studied NPs. Further, the eco-coronas did not affect the particle uptake, suggesting that the reduction in toxicity was related to the particle-organism interaction after eco-corona formation. In a broader context, this implies that although the increasing use and production of NPs may constitute a novel, global environmental threat, the acute toxicity and long-term effects of some NPs will, at least under certain conditions, be reduced as they enter natural ecosystems.
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| 30. |
- Fuertes, Nuria
(författare)
-
Use of localised techniques to elucidate the influence of process variables on the corrosion of stainless steels
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Several factors during steel manufacture and fabrication can alter the passivity and corrosion behaviour of stainless steels. These include alloying, deformation, welding and heat treatments.In this work a combination of local techniques, such as Scanning Vibrating Electrode Technique (SVET) and Scanning Kelvin Probe Force Microscopy (SKPFM), and surface and microstructural analytical techniques, such as Electron Backscatter Diffraction (EBSD), Auger Electron Spectroscopy (AES) and X-ray Photoelectron Spectroscopy (XPS) is used to elucidate the influence of process variables on the corrosion resistance of stainless steels. Different manufacturing processes, such as casting, rolling or additive manufacturing (AM) (Paper V), fabrication processes, such as welding (Paper III) and deformation (Paper I and IV), and post-processing, such as heat and high pressure treatments (Paper II and V) and post-weld cleaning (Paper II) are studied.The results showed that deformation can have a major impact on microstructure but a smaller impact on corrosion. Plastic deformation decreased irreversibly the Volta potential, whereas elastic deformation did not have any permanent effect. The potential was dependent on composition, passive film thickness and deformation but not on the crystallographic orientation. Thermal oxides formed after welding were detrimental to corrosion resistance. SVET showed anodic activity on the weld areas with oxides where pitting initiated, explained by the interplay between the composition and the thickness of the oxides. Brushing combined with pickling was recommended for restoring the corrosion resistance. Long-term ageing of a Cu-alloyed 2507 caused precipitation of Cu-rich ε particles which showed the lowest potential and were most severely pitted, plus nitrides which were the most noble. Intermetallic sigma phase observed in the AM 2507 after HIP heat treatment with slow cooling resulted in a decreased corrosion resistance. However, it was concluded that AM 2507 exhibits similar or even higher corrosion resistance than conventional 2507 if appropriate post-processing parameters are applied.This thesis provides scientific insights to facilitate the correct manufacturing, fabrication and use of stainless steels.
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| 31. |
- Garfias González, Karla Itzel, et al.
(författare)
-
Surface modification of aramid fiber meshes - the key to chemically recyclable epoxy composites
- 2023
-
Ingår i: RSC Sustainability. - : Royal Society of Chemistry (RSC). - 2753-8125. ; 1:8, s. 1967-1981
-
Tidskriftsartikel (refereegranskat)abstract
- The higher chemical sensitivity of aramid fibers, compared to carbon or glass fibers, adds to the challenge of designing recyclable aramid fiber reinforced polymer composites. Our study sheds some light on this endeavor through a surface functionalization approach. Twaron® aramid fibers were surface modified by self-polymerization of dopamine followed by the condensation of a silane coupling agent, bearing an epoxy group (PDA-Si). Thanks to the mild modification process, the fibers retained their thermal and mechanical properties. At the same time, the functionalization enhanced the adhesion strength between the meshes and a partially bio-based epoxy thermoset, which was demonstrated by a peeling adhesion test and lap-shear bonding test. Chemical recycling of the epoxy thermoset and epoxy composites reinforced with PDA-Si aramid meshes was achieved by mild solvolysis in ethylene glycol. The recycled thermoset was rich in hydroxyl groups, which promoted the adhesion with PDA-Si meshes. Furthermore, high-quality PDA-Si aramid meshes were recovered after the chemical recycling. The recovered meshes showed 82% removal of the thermoset matrix and the retention of the surface functionalization as suggested by thermogravimetric and spectroscopic analyses, respectively. This enabled 78% recovery of the initial interface strength between the recycled PDA-Si meshes and virgin thermoset matrix. This unveils the role of surface functionalization not only as a performance enhancer but also as a useful aid in the development of circular FRPCs.
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| 32. |
- Gliga, Anda R., et al.
(författare)
-
Silver nanoparticles modulate lipopolysaccharide-triggered Toll-like receptor signaling in immune-competent human cell lines
- 2020
-
Ingår i: Nanoscale Advances. - : ROYAL SOC CHEMISTRY. - 2516-0230. ; 2:2, s. 648-658
-
Tidskriftsartikel (refereegranskat)abstract
- Silver (Ag) nanoparticles are commonly used in consumer products due to their antimicrobial properties. Here we studied the impact of Ag nanoparticles on immune responses by using cell lines of monocyte/macrophage and lung epithelial cell origin, respectively. Short-term experiments (24 h) showed that Ag nanoparticles reduced the lipopolysaccharide (LPS)-induced secretion of pro-inflammatory cytokines in THP-1 cells under serum-free conditions. ICP-MS analysis revealed that cellular uptake of Ag was higher under these conditions. Long-term exposure (up to 6 weeks) of BEAS-2B cells to Ag nanoparticles also suppressed pro-inflammatory cytokine production following a brief challenge with LPS. Experiments using reporter cells revealed that Ag nanoparticles as well as AgNO3 inhibited LPS-triggered Toll-like receptor (TLR) signaling. Furthermore, RNA-sequencing of BEAS-2B cells indicated that Ag nanoparticles affected TLR signaling pathways. In conclusion, Ag nanoparticles reduced the secretion of pro-inflammatory cytokines in response to LPS, likely as a result of the release of silver ions leading to an interference with TLR signaling. This could have implications for the use of Ag nanoparticles as antibacterial agents. Further in vivo studies are warranted to study this.
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| 33. |
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| 34. |
- Guo, Pengfei, et al.
(författare)
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Chloride Induced Secondary Passive Film Failure for Laser Additive Manufacturing Nickel-Based Superalloys during Electrochemical Machining
- 2023
-
Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 0013-4651 .- 1945-7111. ; 170:6
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated the influence of chloride on the secondary passive film (SPF) on laser directed energy deposition Alloy 718 during electrochemical machining. The results show that SPF formed in chloride-containing electrolyte is more defective than that formed in chloride-free solution, due to the stepped-up cation ejection by chloride. Chloride accelerates the SPF failure via enhanced cation vacancy condensation, SPF dissolution and possibly via surface vacancy pairs' coalescence, restraining the formation of CrO3 and inducing a better surface quality than does the chloride-free electrolyte. Based on the Point Defect Model, a mechanism describing the influence of chloride on SPF was developed.
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| 35. |
- Gupta, G., et al.
(författare)
-
Cobalt nanoparticles trigger ferroptosis-like cell death (oxytosis) in neuronal cells : Potential implications for neurodegenerative disease
- 2020
-
Ingår i: The FASEB Journal. - : Wiley. - 0892-6638 .- 1530-6860. ; 34:4, s. 5262-5281
-
Tidskriftsartikel (refereegranskat)abstract
- The neurotoxicity of hard metal-based nanoparticles (NPs) remains poorly understood. Here, we deployed the human neuroblastoma cell line SH-SY5Y differentiated or not into dopaminergic- and cholinergic-like neurons to study the impact of tungsten carbide (WC) NPs, WC NPs sintered with cobalt (Co), or Co NPs versus soluble CoCl2. Co NPs and Co salt triggered a dose-dependent cytotoxicity with an increase in cytosolic calcium, lipid peroxidation, and depletion of glutathione (GSH). Co NPs and Co salt also suppressed glutathione peroxidase 4 (GPX4) mRNA and protein expression. Co-exposed cells were rescued by N-acetylcysteine (NAC), a precursor of GSH, and partially by liproxstatin-1, an inhibitor of lipid peroxidation. Furthermore, in silico analyses predicted a significant correlation, based on similarities in gene expression profiles, between Co-containing NPs and Parkinson's disease, and changes in the expression of selected genes were validated by RT-PCR. Finally, experiments using primary human dopaminergic neurons demonstrated cytotoxicity and GSH depletion in response to Co NPs and CoCl2 with loss of axonal integrity. Overall, these data point to a marked neurotoxic potential of Co-based but not WC NPs and show that neuronal cell death may occur through a ferroptosis-like mechanism.
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| 36. |
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| 37. |
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| 38. |
- Hedberg, Jonas, 1979-, et al.
(författare)
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Improving the life cycle impact assessment of metal ecotoxicity : Importance of chromium speciation, water chemistry, and metal release
- 2019
-
Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 11:6
-
Tidskriftsartikel (refereegranskat)abstract
- Investigations of metal ecotoxicity in life cycle assessment (LCA) and life cycle impact assessment (LCIA) are becoming important tools for evaluating the environmental impact of a product or process. There is, however, improvement needed for LCIA of metal ecotoxicity in order to make this assessment more relevant and robust. In this work, three issues within the LCIA of metal ecotoxicity are investigated, mainly focusing on topics related to stainless steel manufacturing. The first issue is the importance of considering regional water chemistry when constructing the characterization factor (CF). A model freshwater of relevance for stainless steel manufacturing in a region of Sweden was created with chemistry different from available options. The second issue is related to the lack of consideration on changes in speciation of Cr(VI) in freshwater for a given emission, as Cr(VI) to some extent will be reduced to Cr(III). Two new options are suggested based on relationships between the Cr(VI)-total Cr ratio as a way to improve the relevancy of LCIA for Cr(VI) in freshwater. The last issue is how to treat metal release from slags in LCIA. Metal release from slags was shown to vary significantly between different ways of modelling slag emissions (differences in total metal content, slag leaching tests, estimated emissions to groundwater). © 2019 by the authors.
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| 39. |
- Hedberg, Jonas, 1979-, et al.
(författare)
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In the Search for Nanospecific Effects of Dissolution of Metallic Nanoparticles at Freshwater-Like Conditions : A Critical Review
- 2019
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 53:8, s. 4030-4044
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Tidskriftsartikel (refereegranskat)abstract
- Knowledge on relations between particle properties and dissolution/transformation characteristics of metal and metal oxide nanoparticles (NPs) in freshwater is important for risk assessment and product development. This critical review aims to elucidate nanospecific effects on dissolution of metallic NPs in freshwater and similar media. Dissolution rate constants are compiled and analyzed for NPs of silver (Ag), copper (Cu), copper oxide/hydroxide (CuO, Cu(OH) 2 ), zinc oxide (ZnO), manganese (Mn), and aluminum (Al), showing largely varying (orders of magnitude) constants when modeled using first order kinetics. An effect of small primary sizes (<15 nm) was observed, leading to increased dissolution rate constants and solubility in some cases. However, the often extensive particle agglomeration can result in reduced nanospecific effects on dissolution and also an increased uncertainty related to the surface area, a parameter that largely influence the extent of dissolution. Promising ways to model surface areas of NPs in solution using fractal dimensions and size distributions are discussed in addition to nanospecific aspects related to other processes such as corrosion, adsorption of natural organic matter (NOM), presence of capping agents, and existence of surface defects. The importance of the experimental design on the results of dissolution experiments of metal and metal oxide NPs is moreover highlighted, including the influence of ionic metal solubility and choice of particle dispersion methodology.
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| 40. |
- Hedberg, Jonas, 1979-, et al.
(författare)
-
Transformation of silver nanoparticles released from skin cream and mouth spray in artificial sweat and saliva solutions : particle size, dissolution, and surface area
- 2020
-
Ingår i: Environmental Science and Pollution Research. - : Springer Science and Business Media Deutschland GmbH. - 0944-1344 .- 1614-7499.
-
Tidskriftsartikel (refereegranskat)abstract
- The use of silver nanoparticles (Ag NPs) in consumer products can result in diffuse environmental dispersion of both NPs and ionic silver. This study investigated the transformation of Ag NPs present in two consumer products (skin cream, mouth spray) in terms of release of Ag NPs and ionic silver and changes in particle size in artificial sweat and saliva solutions. Large differences in silver release were observed with the smaller sized Ag NPs in mouth spray releasing more silver compared with the Ag NPs of the skin cream. Substantial particle agglomeration took place in both artificial sweat and saliva, forming large-sized agglomerates (> 100 nm). The amount of dissolved silver in solution after 24 h was less than 10% of the total amount of Ag NPs for both products. The results show that the Ag NPs of these consumer products will largely remain as NPs even after 24 h of skin or saliva contact. The use of normalization by geometric surface area of the particles was tested as a way to compare dissolution for Ag NPs of different characteristics, including pristine, bare, as well as PVP-capped Ag NPs. Normalization of silver dissolution with the geometric surface area was shown promising, but more extensive studies are required to unambiguously conclude whether it is a way forward to enable grouping of the dissolution behavior of Ag NPs released from consumer products.
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| 41. |
- Hedberg, Jonas, 1979-, et al.
(författare)
-
Tungsten carbide nanoparticles in simulated surface water with natural organic matter : dissolution, agglomeration, sedimentation and interaction with Daphnia magna
- 2017
-
Ingår i: Environmental Science: Nano. - : Royal Society of Chemistry. - 2051-8153 .- 2051-8161. ; 4:4, s. 886-894
-
Tidskriftsartikel (refereegranskat)abstract
- Even though anthropogenic nano-sized tungsten carbide nanoparticles (WC NPs) have been found in the environment, there are currently no investigations on their environmental fate. This work studies the interaction between natural organic matter (NOM) and WC NPs, as well as the potential uptake by the aquatic model organism Daphnia magna. We here show that the affinity between WC NPs and humic acid or dihydroxybenzoic acid (DHBA), which are model molecules of NOM, is very low with no observed surface adsorption. The lack of a stabilizing effect of these organic molecules, in combination with a relatively high effective density of WC NP agglomerates in humic acid, resulted in the substantial agglomeration and sedimentation of the WC NPs. A higher stability of the smaller sized WC NP agglomerates (<150 nm) means that this fraction is mobile and can be transported to other settings, suggesting that this particle fraction should be considered in further studies. The dissolution of tungsten from WC NPs was continuous and the relatively slow dissolution rate (on the order of 0.03 mg m-2 h-1) implies that particle transport will not be severely limited from a dissolution perspective. Uptake of tungsten (dissolved tungsten and WC particles) by D. magna was observed although this did not induce any acute toxic effects.
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| 42. |
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| 43. |
- Hedberg, Yolanda, 1985-, et al.
(författare)
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Interaction of Albumin and Fibrinogen with Stainless Steel : Influence of Sequential Exposure and Protein Aggregation on Metal Release and Corrosion Resistance
- 2017
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Ingår i: Corrosion. - : NATL ASSOC CORROSION ENG. - 0010-9312 .- 1938-159X. ; 73:12
-
Tidskriftsartikel (refereegranskat)abstract
- Corrosion and metal release mechanisms of the biomedical stainless steel grade Type 316L are at human-relevant biological conditions not fully understood. This study focuses on its corrosion properties and release of iron (Fe), chromium (Cr), manganese (Mn), and nickel (Ni) into simulated physiological solutions at pH 7.4 in the presence of proteins. Parallel studies were performed on stainless steel Type 303 containing a substantial amount of MnS inclusions. Metal release studies were performed in phosphate buffered saline (PBS) for 4 h and 24 h at 37 degrees C with or without different concentrations of bovine serum albumin (BSA), fibrinogen from bovine plasma (Fbn), or mixtures of the same. Studies were in addition performed after 1, 4, 6, and 24 h in solutions that were partially replenished after 5 h in order to investigate whether any Vroman effect (exchange of adsorbed proteins by proteins of higher binding affinity) could influence the extent of released metals in solution. This was performed at physiological concentrations of BSA (40 g/L) and Fbn (2.67 g/L) in PBS, and for reference solutions of PBS, PBS with 40 g/L BSA, and PBS with 2.67 g/L Fbn. Changes in open-circuit potential and linear polarization resistance were investigated for the same conditions. After exposure, the exposed surfaces were rinsed and investigated ex situ by means of x-ray photoelectron spectroscopy and infrared reflection absorption spectroscopy. Metal-protein complexation-induced metal release mechanisms were found to be most pronounced for Type 316L and the release of Fe, Cr, and Ni. Fibrinogen adsorbed differently onto Type 303 (thicker conformation of adsorbed proteins) as compared with Type 316L and occasionally induced corrosion events for Type 303. Mn was mostly released from inclusions present in the Type 303 alloy, most probably via non-electrochemical mechanisms. A Vroman effect was observed for both grades. A significant extent of precipitation of metal-rich protein aggregates influenced the metal release measurements in solution and resulted in an underestimation of the total amount of released metals from the stainless steel grades.
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| 44. |
- Hedberg, Yolanda, Docent, 1985-, et al.
(författare)
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Mechanistic insight on the combined effect of albumin and hydrogen peroxide on surface oxide composition and extent of metal release from Ti6Al4V
- 2019
-
Ingår i: Journal of Biomedical Materials Research - Part B Applied Biomaterials. - : WILEY. - 1552-4973. ; 107:3, s. 858-867
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Tidskriftsartikel (refereegranskat)abstract
- The titanium–aluminium (6 wt%)–vanadium (4 wt%) (Ti6Al4V) alloy is widely used as an orthopedic and dental implant material due to its high corrosion resistance in such environments. The corrosion resistance is usually determined by means of electrochemical methods, which may not be able to detect other chemical surface reactions. Literature findings report a synergistic effect of the combination of the abundant protein albumin and hydrogen peroxide (H 2 O 2 ) on the extent of metal release and corrosion of Ti6Al4V. The objectives of this study were to gain further mechanistic insight on the interplay of H 2 O 2 and albumin on the metal release process of Ti6Al4V with special focus on (1) kinetics and (2) H 2 O 2 and albumin concentrations. This was accomplished mainly by metal release and surface oxide composition investigations, which confirmed the combined effect of H 2 O 2 and albumin on the metal release process, although not detectable by electrochemical open circuit potential measurements. A concentration of 30 mM H 2 O 2 induced substantial changes in the surface oxide characteristics, an oxide which became thicker and enriched in aluminum. Bovine serum albumin (BSA) seemed to be able to deplete this aluminum content from the outermost surface or at least to delay its surface enrichment. This effect increased with increased BSA concentration, and for time periods longer than 24 h. This study hence suggests that short-term (accelerated) corrosion resistance measurements are not sufficient to predict potential health effects of Ti6Al4V alloys since also chemical dissolution mechanisms play a large role for metal release, possibly in a synergistic way.
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| 45. |
- Hedberg, Yolanda, 1985-, et al.
(författare)
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Nanoparticles of WC-Co, WC, Co and Cu of relevance for traffic wear particles – Particle stability and reactivity in synthetic surface water and influence of humic matter
- 2017
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Ingår i: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 224, s. 275-288
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Tidskriftsartikel (refereegranskat)abstract
- Studded tyres made of tungsten carbide cobalt (WC-Co) are in the Northern countries commonly used during the winter time. Tungsten (W)-containing nano- and micron-sized particles have been detected close to busy roads in several European countries. Other typical traffic wear particles consist of copper (Cu). The aims of this study were to investigate particle stability and transformation/dissolution properties of nanoparticles (NPs) of WC-Co compared with NPs of tungsten carbide (WC), cobalt (Co), and Cu. Their physicochemical characteristics (primarily surface oxide and charge) are compared with their extent of sedimentation and metal release in synthetic surface water (SW) with and without two different model organic molecules, 2,3- and 3,4-dihydroxybenzoic acid (DHBA) mimicking certain sorption sites of humic substances, for time periods up to 22 days. The WC-Co NPs possessed a higher electrochemical and chemical reactivity in SW with and without DHBA molecules as compared with NPs of WC, Co, and Cu. Co was completely released from the WC-Co NPs within a few hours of exposure, although it remained adsorbed/bonded to the particle surface and enabled the adsorption of negatively charged DHBA molecules, in contrast with the WC NPs (no adsorption of DHBA). The DHBA molecules were found to rapidly adsorb on the Co and Cu NPs. The sedimentation of the WC and WC-Co NPs was not influenced by the presence of the 2,3- or 3,4-DHBA molecules. A slight influence (slower sedimentation) was observed for the Co NPs, and a strong influence (slower sedimentation) was observed for the Cu NPs in SW with 2,3-DHBA compared with SW alone. The extent of metal release increased in the order: WC < Cu < Co < WC-Co NPs. All NPs released more than 1 wt-% of their metal total mass. The release from the Cu NPs was most influenced by the presence of DHBA molecules.
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| 46. |
- Hedberg, Yolanda, 1985-, et al.
(författare)
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Protective green patinas on copper in outdoor constructions
- 2011
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Ingår i: Journal of Environmental Protection. - : Scientific Research Publishing, Inc.. - 2152-2197 .- 2152-2219. ; 2:7, s. 956-959
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Tidskriftsartikel (refereegranskat)abstract
- The last 15 years of research related to atmospheric corrosion and the release of copper to the environment are shortly summarized. Brown and green patinas with high barrier properties for corrosion are gradually evolved on copper at atmospheric conditions. The corrosion process and repeated dry and wet cycles results in a partial dissolution of cor-rosion products within the patina. Dissolved copper can be released and dispersed into the environment via the action of rainwater, however the major part is rearranged within the patina during drying cycles. The majority of corrosion products formed have a poor solubility, very different from water soluble copper salts. The release process is very slow and takes place independent of patina color. Its extent has only a marginal effect on the adherent patina. Released cop-per rapidly interacts with organic matter and in contact with different surfaces already in the close vicinity of the building, such as drainage systems, storm water pipes, pavements, stone materials and soil systems. These surfaces all have high capacities to retain copper in the runoff water and to reduce its concentration and chemical form to non-available and non-toxic levels for aquatic organisms.
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| 47. |
- Hedberg, Yolanda, Docent, 1985-, et al.
(författare)
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Surface modified Ti6Al4V for enhanced bone bonding ability - Effects of silver and corrosivity at simulated physiological conditions from a corrosion and metal release perspective
- 2020
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Ingår i: Corrosion Science. - : Elsevier. - 0010-938X .- 1879-0496. ; 168
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Tidskriftsartikel (refereegranskat)abstract
- Different surface treatments, with and without silver (Ag), of a Ti6Al4V alloy for increased bone bonding ability were investigated and compared with non-treated surfaces. Studies were conducted at 37 degrees C in phosphate buffered saline (PBS, pH 7.4) of varying hydrogen peroxide (H2O2) and bovine serum albumin (BSA) concentrations. Increased levels of metal release and corrosion were observed in the presence of both H2O2 and BSA due to complexation with Ti and Al in the surface oxide, respectively. Ag release was enhanced by the presence of BSA. Galvanic effects by Ag were minor, but possibly observed in the most corrosive environment.
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| 48. |
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| 49. |
- Hedberg, Yolanda, Docent, 1985-, et al.
(författare)
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Welding fume nanoparticles from solid and flux-cored wires : Solubility, toxicity, and role of fluorides
- 2021
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Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 413
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Tidskriftsartikel (refereegranskat)abstract
- Welding fume particles are hazardous. Their toxicity likely depends on their composition and reactivity. This study aimed at exploring the role of sodium or other fluorides (NaF), which are intentionally added to flux-cored wire electrodes for stainless steel welding, on the solubility (in phosphate buffered saline) and toxicity of the generated welding fume particles. A multi-analytical particle characterization approach along with in-vitro cell assays was undertaken. The release of Cr(VI) and Mn from the particles was tested as a function of fluoride solution concentration. The welding fume particles containing NaF released significantly higher amounts of Cr (VI) compared with solid wire reference fumes, which was associated with increased cytotoxicity and genotoxicity in-vitro. No crystalline Na or potassium (K) containing chromates were observed. Cr(VI) was incorporated in an amorphous mixed oxide. Solution-added fluorides did not increase the solubility of Cr(VI), but contributed to a reduced Mn release from both solid and flux-cored wire fume particles and the reduction of Cr (VI) release from solid wire fume particles. Chemical speciation modeling suggested that metal fluoride complexes were not formed. The presence of NaF in the welding electrodes did not have any direct, but possibly an indirect, role in the Cr(VI) solubility of welding fumes.
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| 50. |
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