Sökning: "NIR FT Raman spectroscopy"

Hittade 4 avhandlingar innehållade orden NIR FT Raman spectroscopy.

  1. 1. Mercerization and Enzymatic Pretreatment of Cellulose in Dissolving Pulps

    Författare :Heléne Almlöf Ambjörnsson; Ulf Germgård; Thomas Nilsson; Storker Moe; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; alkali; carboxymethyl cellulose; cellulose I; cellulose II; cellulose dissolution; degree of substitution; enzymatic treatment; filterability; gel formation; mercerization; multivariate analytical methods; NIR FT Raman spectroscopy; sodium hydroxide; zink oxide; Chemical Engineering; Kemiteknik;

    Sammanfattning : This thesis deals with the preparation of chemically and/or enzymatically modified cellulose. This modification can be either irreversible or reversible. Irreversible modification is used to prepare cellulose derivatives as end products, whereas reversible modification is used to enhance solubility in the preparation of regenerated cellulose. LÄS MER

  3. 2. Extended Mercerization Prior to Carboxymethyl Cellulose Preparation

    Författare :Heléne Almlöf; Ulf Germgård; Björn Kreutz; Monica Ek; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carboxymethyl cellulose; Mercerization; DS; FT Raman spectroscopy; Filtration ability; Chemical engineering; Kemiteknik; Chemical Engineering; Kemiteknik;

    Sammanfattning : Carboxymethyl cellulose (CMC) is produced commercially in a two-stage process consisting of a mercerization stage, where the pulp is treated with alkali in a water alcohol solution, followed by an etherification stage in which monochloroacetic acid is added to the pulp slurry. In this thesis an extended mercerization stage of a spruce ether pulp was investigated where the parameters studied were the ratio of cellulose I and II, concentration of alkali, temperature and retention time. LÄS MER

  4. 3. Surface reactions in aqueous suspensions of fluorapatite and iron oxides

    Författare :Mathias Jarlbring; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry of Interfaces; Gränsytors kemi;

    Sammanfattning : The main objectives have been to study and model surface reactions of aqueous suspen-sions of minerals with relevance to the dephosphorization of iron oxides by reverse froth flotation. Synthetic hematite, maghemite and fluorapatite in colloidal forms were prepared and thoroughly characterized using XRD, SEM, BET, FT-IR and FT-Raman. LÄS MER

  5. 4. Analytical techniques for quality assessment of separated and commingled recycled polymer fractions

    Författare :Walker Camacho; KTH; []
    Nyckelord :recycling; hdpe; pp; blends; nylon 6.6; abs; water content; mae; gc-ms; mir; chemiluminiscence;

    Sammanfattning : Different methods for quality assessment of separated andcommingled plastics from household and electronic waste havebeen developed. Especial attention has been given tospectroscopic methods since they are non-destructive andrequire little or no sample preparation at all. LÄS MER