Sökning: "kristallografi"

Visar resultat 11 - 15 av 17 avhandlingar innehållade ordet kristallografi.

  1. 11. Nanoscale Crystal Growth: The Importance of Interfaces and Phase Boundaries Kristallväxt på Nanometer Skala: Vikten av Ytor och Gränser

    Författare :Brent Wacaser; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; kristallografi; fasjämvikt; Semiconductory physics; Halvledarfysik; thermal and mechanical properties; crystallography; phase equilibria; Kondenserade materiens egenskaper:struktur; egenskaper termiska och mekaniska ; Condensed matter:stucture; Fysik; Physics; epitaxy; VLS; MOVPE; CBE; nanostructures; crystal growth; nanowires; III-V semiconductors; growth mechanism; MBE; Material technology; Materiallära; materialteknik;

    Sammanfattning : Surfaces and interfaces have a special significance to nanotechnology because the surface/volume ratio of nanomaterials is larger than for bulk materials. Therefore, interfaces of nanomaterials are usually more important to the properties of nanomaterials than for larger scale materials. LÄS MER

  3. 12. A study of the stereochemistry and electronic transitions of cyclic and acyclic thioamides by crystallography, spectroscopy and computational methods

    Författare :Knut Rang; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; UV and CD spectroscopy; rotational barriers; DNMR; X-ray; N -bis[ S -1-phenylethyl]-thiourea; N; attractive steric effect; chiral; phenyl or H- rhodanines; 3- alkyl or aralkyl -5- methyl; Conformations; electronic transitions; molecular mechanics; enantiom; Organic chemistry; Organisk kemi;

    Sammanfattning : Analysis of conformations and electron transitions of 3-(alkyl or aralkyl)-5-(methyl or phenyl)rhodanines with analogues and N,N'-bis[(S)-1-phenylethyl]-thiourea have been performed by X-ray crystallography, 1H NMR, molecular mechanics, ultraviolet spectroscopy and for the chiral rhodanines, enantiomer chromatography and circular dichroism spectroscopy. The magnitude of rotational barriers has been determined. LÄS MER

  4. 13. From Time-Averaged to Time-Resolved Crystallography: Studies on Superoxide Dismutase and Myoglobin

    Författare :Thomas Ursby; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; superoxide dismutase; Bayesian statistics; electron difference maps; synchrotron; docking site; photolysis; myoglobin; Time-resolved crystallography; Laue; thermostability; Sulfolobus solfataricus; Molecular biophysics; Molekylär biofysik;

    Sammanfattning : We have studied protein motions with nanosecond time-resolved crystallography. The release of carbon monoxide from its complex with myoglobin (MbCO) was triggered by nanosecond laser pulses. X-ray data were collected with time delays ranging from 4 ns to 1.9 ms using the Laue method, at the European Synchrotron Radiation Facility in Grenoble. LÄS MER

  5. 14. Insights into structure and dynamics of the AAA+ motor of magnesium chelatase

    Författare :Joakim Lundqvist; Biokemi och Strukturbiologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bioinformatik; biomathematics biometrics; Bioinformatics; medical informatics; Rhodobacter capsulatus; Tetrapyrrole; Mutants; Magnesium chelatase; Cryo-Electron microscopy single-particle 3D reconstruction; Chlorophyll biosynthesis; AAA proteins; ATPase; medicinsk informatik; biomatematik; Molecular biophysics; Molekylär biofysik; Natural science; Naturvetenskap;

    Sammanfattning : The insertion of Mg2+ into protoporphyrin IX represents the first committed step in the chlorophyll and bacteriochlorophyll biosynthetic pathways. The reaction is catalyzed by the multisubunit enzyme Mg-chelatase, which consists of three subunits, known as I (molecular weight ~40 kDa), D (~70 kDa), and H (~140 kDa). LÄS MER

  7. 15. Magnesium Chelatase - a Key Enzyme in Chlorophyll Biosynthesis

    Författare :Eva Axelsson; Biokemi och Strukturbiologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kemi; Chemistry; AAA-proteins; Chlorophyll biosynthesis; Magnesium chelatase;

    Sammanfattning : The biosynthesis of chlorophylls is an important process in nature. The green pigments play a fundamental role in absorbing and transferring solar energy to the photosynthetic apparatus. LÄS MER