Sökning: "Precipitate"

Visar resultat 6 - 10 av 104 avhandlingar innehållade ordet Precipitate.

1. 6. Alloy Design and Characterization of γ′ Strengthened Nickel-based Superalloys for Additive Manufacturing

   Författare :Jinghao Xu; Johan Moverare; Ru Lin Peng; Eric Jägle; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nickel-based superalloy; Alloy design; Laser powder bed fusion; Cracking susceptibility; Additive manufacturability; Heat treatment; γ′ precipitate; High-temperature mechanical property; Creep.;

   Sammanfattning : Nickel-based superalloys, an alloy system bases on nickel as the matrix element with the addition of up to 10 more alloying elements including chromium, aluminum, cobalt, tungsten, molybdenum, titanium, and so on. Through the development and improvement of nickel-based superalloys in the past century, they are well proved to show excellent performance at the elevated service temperature. LÄS MER

3. 7. Fullerene γ-Cyclodextrin Complexes

   Författare :Thomas Andersson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; C60; a-cyclodextrin; aggregates; FAB LSIMS; Buckminsterfullerene; g-cyclodextrin; b-cyclodextrin; ring-currents; fullerene; host-guest; C70;

   Sammanfattning : The fullerenes, C60 and C70, can form inclusion complexes with .gamma.-cyclodextrin as the host. The complexes are formed by refluxing a water solution of . LÄS MER

4. 8. Ethanol from lignocellulose : Alkali detoxification of dilute-acid spruce hydrolysates

   Författare :Björn Alriksson; Karlstads universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; Biokemi; Kemi; Chemistry;

   Sammanfattning : Detoxification of dilute-acid lignocellulose hydrolysates by treatment with Ca(OH)2 (overliming) efficiently improves the production of fuel ethanol, but is associated with drawbacks like sugar degradation and CaSO4 precipitation. In factorial designed experiments, in which pH and temperature were varied, dilute-acid spruce hydrolysates were treated with Ca(OH)2, NH4OH or NaOH. LÄS MER

5. 9. Model for activity coefficients and solubilities of Na2CO3 and Na2SO4 in high-temperature solutions

   Författare :Marta Anna Bialik; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; scaling; Pitzer model; activity coefficient; solubility; sodium carbonate; sodium sulfate; boiling point raise; double salt; solid solution; burkeite;

   Sammanfattning : Scaling of sodium sulfate and sodium carbonate double salts has long been recognized as a problem in the black liquor evaporation process. These salts are abundant in black liquor and often tend to precipitate on heat transfer areas, thereby significantly decreasing the heat transfer efficiency. LÄS MER

7. 10. Evolution of Microstructure in Two Austenitic Alloys at High Temperatures

   Författare :Jenny M Erneman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; N ; Thermo-Calc; Nb C; gamma prime; DICTRA; APFIM; quantitative metallography; AISI 347; Alloy 800; energy filtered TEM; sigma phase;

   Sammanfattning : A niobium stabilised AISI 347 austenitic stainless steel was investigated after static ageing and creep deformation at temperatures between 500°C and 800°C for times up to 88 000 h. Coarse and fine NbX precipitates and also s-phase precipitates were formed in the temperature range 500-700°C. LÄS MER