Sökning: "Yolanda Hedberg"

Hittade 5 avhandlingar innehållade orden Yolanda Hedberg.

  1. 1. Environmental and health aspects of corrosion– importance of chemical speciation

    Författare :Yolanda Hedberg; Inger Odnevall Wallinder; Anna Karin Borg Karlsson; Susanna Wold; KTH; []
    Nyckelord :;

    Sammanfattning : During the last decades, the interest in corrosion of metals and alloys from an environmental and health perspective has increased rapidly as a consequence of stricter environmental and human exposure legislations, their extensive use as implant materials and an increasing understanding related to occupational and/or daily exposure to airborne particles. Corrosion-induced metal release, however, needs to be understood in detail and to include knowledge related to chemical speciation, i. LÄS MER

  2. 2. Stainless Steel in Biological Environments – Relation between Material Characteristics, Surface Chemistry and Toxicity

    Författare :Yolanda Hedberg; Inger Odnevall Wallinder; Sasha Omanovich; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Triggered by the regulatory need of the industry to demonstrate safe use of their alloy products from an environmental and health perspective, and by the significant lack of metal release data and its correlation to material and surface characteristics for iron- and chromium-based alloys, a highly interdisciplinary in-depth research effort was undertaken to assess the relation between material/surface characteristics and toxicity with main emphasis on stainless steel alloys. This thesis focuses predominantly on studies made on AISI 316L both as massive sheet and as powder particles, but includes also results for other stainless steel grades and reference metals and metal oxides. LÄS MER

  3. 3. Use of local electrochemical techniques for corrosion studies of stainless steels

    Författare :Nuria Fuertes; Rachel Pettersson; Mari Sparr; Ulf Kivisäkk; Yolanda Hedberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stainless steel; passive film; thermal oxides; work function; pickling; SKPFM; SVET; XPS; AES; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : The excellent corrosion resistance of stainless steels arises from the presence of a passive film on its surface. Above 10.5wt% Cr a chromium oxide of 1-3 nm is formed on the surface of the metal that in case of damage will reform and hinder further dissolution of the metal. LÄS MER

  4. 4. Bioaccessibility, corrosion and surface properties of metals, alloys and metallic powder in biological fluids of relevance for occupational and consumer health hazard assessment

    Författare :Xuying Wang; Inger Odnevall Wallinder; Yolanda S. Hedberg; Lars Nyborg; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Metal and alloy; metal release; synthetic biological fluids; surface oxide; corrosion resistance; hazard assessment; Kemi; Chemistry;

    Sammanfattning : When assessing hazards of metals, alloys, and metal-containing items, the metal release (bioaccessibility) is of high importance. Triggered by increasingly stricter hazard classifications for metals, especially cobalt (Co), and limited knowledge, the aim of this doctoral thesis is to assess correlations between the metal/alloy surface characteristics, corrosion and metal release pattern in different simulated biological fluids relevant to human exposure scenarios (dermal, ingestion and inhalation, Papers I-V). LÄS MER

  5. 5. Metal release from stainless steel and CoCrMo alloys in protein-rich environments – effects of protein aggregation, friction, and irradiation

    Författare :Zheng Wei; Yolanda Hedberg; Inger Odnevall Wallinder; Daniel Klint; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Metal release; stainless steel; CoCrMo; protein aggregation; friction; irradiation; Vroman effect; Kemi; Chemistry;

    Sammanfattning : Highly corrosion-resistant alloys are used in sensitive environments such as the human body and food environments. However, even tiny amounts of released metals from these surfaces could potentially cause adverse effects. It is hence important to study the biointerface between corrosion-resistant alloys and protein-rich environments. LÄS MER