Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
A vacuum-compatible wet-specimen chamber for compact x-ray microscopy
KTH, School of Engineering Sciences (SCI), Applied Physics.
KTH, School of Engineering Sciences (SCI), Applied Physics.
KTH, School of Engineering Sciences (SCI), Applied Physics.ORCID iD: 0000-0003-2723-6622
2007 (English)In: Journal of Microscopy, ISSN 0022-2720, E-ISSN 1365-2818, Journal of Microscopy, Vol. 226, no 1, 71-73 p.Article in journal (Refereed) Published
Abstract [en]

Soft X-ray microscopy is a powerful tool for investigations of, for example, polymers or soils in their natural liquid environment. This requires a wet-specimen chamber. Compact X-ray microscopy allows the horizontal mounting of such samples, thereby reducing the influence of gravitational forces. We have developed a wet-specimen chamber for such compact X-ray microscope. The chamber is vacuum compatible, which reduces the exposure time. The vacuum sealing is achieved by a combination of mechanical sealing and sealing by bio-compatible glue. With the wet-specimen chamber the specimens can be kept in an aqueous environment in a vacuum of 10(-4) mbar for several hours. Imaging of lipid droplets in water demonstrates the function of the wet-specimen chamber.

Place, publisher, year, edition, pages
2007. Vol. 226, no 1, 71-73 p.
Keyword [en]
compact X-ray microscopy, wet cell, wet-specimen chamber
National Category
Physical Sciences
Identifiers
URN: urn:nbn:se:kth:diva-6204ISI: 000245101000009Scopus ID: 2-s2.0-33947397151OAI: oai:DiVA.org:kth-6204DiVA: diva2:10848
Note
Uppdaterad från manuskript till artikel: 20100920 QC 20100920Available from: 2006-10-03 Created: 2006-10-03 Last updated: 2017-12-14Bibliographically approved
In thesis
1. Compact Soft X-Ray Microscopy: Image Processing and Instrumentation
Open this publication in new window or tab >>Compact Soft X-Ray Microscopy: Image Processing and Instrumentation
2006 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Soft x-ray microscopy is a powerful technique for natural-contrast, high-resolution imaging of organic materials. This Thesis describes new instrumentational and new image-processing methods to improve the image quality of the compact x-ray microscope at the Biomedical & X-Ray Physics division at KTH. The microscope is based on a laser-plasma source combined with different condenser optics, either multilayer mirrors or zone plates. Imaging is performed by micro zone plates. The microscope works in the water window (\lambda = 2.3-4.4 nm), where the attenuation lengths of oxygen and carbon differ strongly, providing high natural contrast for carbon-containing specimens in an aqueous environment.

By optimizing the properties of the laser-plasma source and fabricating multilayer mirrors with high, uniform reflectivity, the performance of the microscope's illumination system could be improved and exposure times decreased significantly to about 2 min for imaging dry samples and 5 min for imaging wet samples. For imaging of wet samples, a wet-specimen chamber was developed, which is vacuum-compatible. Since it is horizontally mounted in the microscope, it offers advantages for investigations in polymer and soil science.

To improve the quality of images taken by the compact x-ray microscope an image-restoration algorithm was developed. Denoising is performed by a filtering algorithm based on the discrete wavelet transform. This algorithm shows advantages compared to Fourier-based algorithms, since the filtering of spatial frequencies is done locally. An improvement in exposure time by a factor of about 2 could be realized without loss of image information.

To stimulate experiments on functional imaging in x-ray microscopy an image-analysis algorithm for identifying colloidal-gold particles was developed. This algorithm is based on a combination of a threshold with respect to the local absorption and a shape discrimination, realized by fitting a Gaussian profile to the potential particles. The algorithm was evaluated and optimized on images taken by the transmission x-ray microscope at BESSY II. The size-selective identification and localization of single gold particles down to a diameter of 50 nm was demonstrated.

Place, publisher, year, edition, pages
Stockholm: KTH, 2006. viii, 51 p.
Series
Trita-FYS, ISSN 0280-316X ; 2006:60
Keyword
X-ray microscopy
National Category
Physical Sciences
Identifiers
urn:nbn:se:kth:diva-4128 (URN)91-7178-458-6 (ISBN)
Public defence
2006-10-20, FD 5, Albanova, 10:30
Opponent
Supervisors
Note
QC 20100920Available from: 2006-10-03 Created: 2006-10-03 Last updated: 2010-09-20Bibliographically approved

Open Access in DiVA

No full text

Other links

ScopusWiley Online Library

Authority records BETA

Hertz, Hans M.

Search in DiVA

By author/editor
Stollberg, HeidePokorny, MilanHertz, Hans M.
By organisation
Applied Physics
In the same journal
Journal of Microscopy
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 54 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf