Sökning: "H2SO4"

Visar resultat 6 - 10 av 25 avhandlingar innehållade ordet H2SO4.

1. 6. The influence of Al alloy microstructure on conversion coating formation

   Författare :Salil Sainis; Caterina Zanella; Ehsan Ghassemali; Jönköping University; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aluminium alloys; cast Al-Si alloys; conversion coating treatment; cerium; localized deposition; surface pre-treatments; microstructure; SEM; FIB-SEM; AFM-SKPFM; aluminiumlegeringar; gjutna Al-Si legeringar; omvandlingsbeläggningar; cerium; lokaliserad deposition; ytförbehandlingar; microstruktur SEM; FIB-SEM; AFM-SKPFM;

   Sammanfattning : The formation of conversion coatings based on Ce, trivalent Cr and Ti/Zr is triggered by the local pH increase at cathodic IM sites of the aluminium alloy microstructure. The pH gradient is created over the cathodic intermetallic (IM) sites of the microstructure and its intensity is influenced by their activity which depends on their chemical composition, their size, and spatial distribution. LÄS MER

3. 7. Process-microstructure-corrosion interrelations for stainless steel

   Författare :David Lindell; Rachel Pettersson; Rebecca L. Higginson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; stainless steel; processing; annealing; pickling; microstructure; corrosion; anisotropy; oxyfuel; Kemi; Chemistry;

   Sammanfattning : Stainless steels were first developed in the early 20th century and have since then emerged as a very diverse class of engineering materials. Along with steels having new combinations of properties, there is a continuous development of new technologies allowing the material to be produced in a faster and more energy effcient manner. LÄS MER

4. 8. Trace Element Analysis with Application to Environmental Pollutants Studies in Vietnam

   Författare :Thi Hong Nguyen; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; blood; environmental samples; discriminant analysis; ICP-MS; coal mining; hair; EDXRF; microwave digestion; CV-AAS; urine; sample preparation; coal combustion;

   Sammanfattning : In the work presented here the attention has been focused on optimising sample preparation and analytical techniques for trace element determination, analytical quality assurance and environmental applications. Trace element concentrations in various environmental matrices were investigated using Energy Dispersive X-ray Fluorescence (EDXRF), Inductively Coupled Plasma Mass Spectro-metry (ICP-MS) and Cold Vapour Atomic Absorption Spectrometry (CV-AAS). LÄS MER

5. 9. Bioethanol Production: Pretreatment and Enzymatic Hydrolysis of Softwood

   Författare :Charlotte Tengborg; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; recirculation of process streams; detoxification; inhibition; hydrolysis conditions; enzymatic hydrolysis; Ethanol production; steam pretreatment; softwood; Carbochemistry; petrochemistry; fuels and explosives technology; Petrokemi; bränslen; sprängämnen;

   Sammanfattning : The enzymatic hydrolysis process can be used to produce bioethanol from softwood, which are the dominating raw material in the Northern hemisphere. This thesis deals with the development of the process focusing on the pretreatment and the enzymatic hydrolysis stages. LÄS MER

7. 10. An Insight into the Critical Role of Microstructure and Surface Preparation on Localized Conversion Coating Deposition on Cast Al Alloys

   Författare :Salil Sainis; Caterina Zanella; Ehsan Ghassemali; Marjorie Olivier; Jönköping University; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aluminium alloys; cast Al-Si alloys; conversion coating treatment; cerium; localized deposition; surface preparation; microstructure; SEM; FIB-SEM; AFM-SKPFM; Aluminiumlegeringar; gjutna Al-Si legeringar; Cerium; lokal deposition; omvandlingsbeläggningsbehandling; förbehandling av yta; mikrostruktur; SEM; FIB-SEM; AFM-SKPFM;

   Sammanfattning : The spontaneous cerium conversion coating formation over aluminium alloys is affected by the chemical process conditions, the surface preparation prior to conversion treatment and the microstructure of the underlying alloy. Most research performed until now focus only on the former whereas the influence of the latter two is poorly understood. LÄS MER