Sökning: "gas volume"

Visar resultat 1 - 5 av 277 avhandlingar innehållade orden gas volume.

  1. 1. Factors Related to the Formation of Gas Porosity in Grey Cast Iron: Investigation of Core Gas Evolution and Gas Concentrations in Molten Iron

    Författare :Jessica Orlenius; [2008]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; core binders; Gas porosity; hydrogen; grey iron; gas absorption; nitrogen; oxygen; gas evolution rate; green sand; mould filling; gas volume; gas solubility;

    Sammanfattning : Since gas porosity is a major casting problem, it is of greatest importance to increase the knowledge about the foundry process in order to minimise the presence of gas porosity and thereby improving the casting quality. Gas porosity is generally considered to originate from gases precipitated during solidification of iron and from entrained gas picked up by the metal during the mould filling. LÄS MER

  2. 2. Endotracheal Suction a Reopened Problem

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Birgitta Almgren; Marieann Högman; Mats Sjöquist; Anders Larsson; [2005]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Physiology; Mechanical; ventilation; endotracheal; suction; lung; volume; loss; gas; exchange; Fysiologi; MEDICINE Physiology and pharmacology Physiology; MEDICIN Fysiologi och farmakologi Fysiologi;

    Sammanfattning : During mechanical ventilation, patients are connected to the ventilator by an endotracheal tube. The tube needs to be cleaned from mucus by suction, which can cause negative effects such as lung collapse, hypoxemia and desaturation. LÄS MER

  3. 3. Large Volume Injection and Hyphenated Techniques for Gas Chromatographic Determination of PBDEs and Carbazoles in Air

    Detta är en avhandling från Stockholm : Institutionen för analytisk kemi

    Författare :Petter Tollbäck; Conny Östman; Tuulia Hyötyläinen; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; large volume injection; hyphenated techniques; LC-GC; GC-MS; mass spectrometry; GC; gas chromatography; carbazoles; PBDE; polybrominated diphenyl ethers; NATURAL SCIENCES Chemistry Analytical chemistry; NATURVETENSKAP Kemi Analytisk kemi;

    Sammanfattning : This thesis is based on studies in which the suitability of various gas chromatography (GC) injection techniques was examined for the determination of polybrominated diphenyl ethers (PBDEs) and carbazoles, two groups of compounds that are thermally labile and/or have high boiling-points. For such substances, it is essential to introduce the samples into the GC system in an appropriate way to avoid degradation and other potential problems. LÄS MER

  4. 4. FRC in acute lung injury. Experimental and clinical studies

    Detta är en avhandling från Stockholm : Institutionen för analytisk kemi

    Författare :Christian Rylander; Göteborgs universitet.; Gothenburg University.; [2005]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Airway obstruction; Acute lung injury; Acute respiratory distress syndrome; Attenuation; Computed tomography; End-expiratory lung volume; Functional residual capacity; Gas dilution; Hounsfield unit; Lung volume; Oleic acid; Recruitment; Time constant;

    Sammanfattning : Respiratory failure due to acute lung injury (ALI) of diffuse inflammatory origin is a major cause of respiratory failure treated in intensive care units. In ALI, FRC is reduced by various mechanisms associated with hypoxemia and consolidation of the lung. LÄS MER

  5. 5. Free Volume and Mesopores in Polymer Nanocomposites

    Detta är en avhandling från KFS AB

    Författare :Petra Winberg; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemical technology and engineering; Kompositmaterial; Composite materials; Macromolecular chemistry; permeability ; membrane ; positron annihilation ; fumed silica ; clay ; mesopores ; polymer nanocomposites ; free volume ; Kemiteknik och kemisk teknologi; Makromolekylär kemi;

    Sammanfattning : The free volume in polymers is coupled to several important physical properties, such as density, viscosity and gas diffusivity. The physical properties of polymers close to a solid surface have been shown to be significantly perturbed as compared to their bulk state. LÄS MER