Sökning: "relative retention time"

Visar resultat 1 - 5 av 20 avhandlingar innehållade orden relative retention time.

  1. 1. Retention time predictions in Gas Chromatography

    Detta är en avhandling från Stockholm : Department of Analytical Chemistry, Stockholm University

    Författare :Yasar Thewalim; Stockholms universitet.; [2011]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; gas chromatography; computer simulation; two-parameter model; retention time prediction; NATURAL SCIENCES Chemistry Analytical chemistry; NATURVETENSKAP Kemi Analytisk kemi; Analytical Chemistry; analytisk kemi;

    Sammanfattning : In gas chromatography, analytes are separated by differences in their partition between a mobile phase and a stationary phase. Temperature-program, column dimensions, stationary and mobile phases, and flow rate are all parameters that can affect the quality of the separation in gas chromatography. LÄS MER

  2. 2. Hydrodynamic control of retention in heterogeneous aquifers and fractured rock

    Detta är en avhandling från Stockholm : KTH

    Författare :Hua Cheng; KTH.; [2005]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aquifer; Fracture; groundwater; First-order solution; Monte-Carlo simulation; Nu-clear waste; Heterogeneity; Retention processes; Matrix diffusion; Prediction; Evaluation; Travel time; Flow rate; ; TECHNOLOGY Civil engineering and architecture Water engineering; TEKNIKVETENSKAP Samhällsbyggnadsteknik och arkitektur Vattenteknik;

    Sammanfattning : In this thesis, fluid flow and solute transport in heterogeneous aquifers and particularly in frac-tured rock have been investigated using Lagrangian Stochastic Advective-Reaction (LaSAR) framework. The heterogeneity of the aquifer structure or fracture configuration, as well as the various reaction/retention processes have been considered in the modelling approach. LÄS MER

  3. 3. Properties and analysis of dioxin-like compounds in marine samples from Sweden

    Detta är en avhandling från Umeå : Kemi

    Författare :Kjell Lundgren; Umeå universitet.; [2003]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; planar dioxin-like compound; polychlorinated dibenzofuran; polychlorinated biphenyl; polychlorinated naphthalene; alkylated polychlorinated dibenzofuran; high-performance liquid chromatography; PX-21 carbon column; biomagnification factor; biota to sediment accumulation factor; fluxes; relative retention time; mass spectrometry; relative response factor; ultra-violet spectroscopy; Miljökemi; NATURAL SCIENCES Chemistry Environmental chemistry; NATURVETENSKAP Kemi Miljökemi; Analytical Chemistry; analytisk kemi;

    Sammanfattning : Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) have been assigned toxic equivalency factors (TEFs). These compounds are today routinely analysed with sophisticated analytical techniques. LÄS MER

  4. 4. Effects of retrieval and articulation on memory

    Detta är en avhandling från Stockholm : Department of Psychology, Stockholm University

    Författare :Max Larsson Sundqvist; Stockholms universitet.; [2017]
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; testing effect; covert retrieval; overt retrieval; judgments of learning; delayed JOL effect; response format; retention interval; psykologi; Psychology;

    Sammanfattning : Many would agree that learning occurs when new information is stored in memory. Therefore, most learning efforts typically focus on encoding processes, such as additional study or other forms of repetition. However, as I will outline in this thesis, there are other means by which to improve memory, such as retrieval practice in the form of tests. LÄS MER

  5. 5. Oxidation of terpenes in indoor environments A study of influencing factors

    Detta är en avhandling från Umeå : Ekologi och geovetenskap

    Författare :Linda Pommer; Umeå universitet.; [2003]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; Monoterpene; Ozone O3 ; Nitrogen dioxide NO2 ; Nitrogen oxide NO ; Relative humidity RH ; Modelling; Scrubber; Experimental design; Interaction; Volatile organic compounds VOC ; Sick buildings syndrome SBS ; Principal component analysis PCA ; Indoor air; Ventilation; Tenax TA; Sodium sulphite; Miljökemi; NATURAL SCIENCES Chemistry Environmental chemistry; NATURVETENSKAP Kemi Miljökemi; Analytical Chemistry; analytisk kemi;

    Sammanfattning : In this thesis the oxidation of monoterpenes by O3 and NO2 and factors that influenced the oxidation were studied. In the environment both ozone (O3) and nitrogen dioxide (NO2) are present as oxidising gases, which causes sampling artefacts when using Tenax TA as an adsorbent to sample organic compounds in the air. LÄS MER