X-ray microscopy of biological specimens with laser plasma x rays

Author(s):  
Kunio Shinohara ◽  
Atsushi Ito ◽  
Yasuhito Kinjo
Keyword(s):  
X Rays ◽  
X Ray ◽  
1999 ◽  
Vol 75 (16) ◽  
pp. 2350-2352 ◽  
Author(s):  
Hidetoshi Nakano ◽  
Yoshinori Goto ◽  
Peixiang Lu ◽  
Tadashi Nishikawa ◽  
Naoshi Uesugi

1988 ◽  
Vol 129 ◽  
Author(s):  
Glenn D. Kubiak ◽  
Duane A. Outka ◽  
John M. Zeigler

ABSTRACTA laser-generated plasma source of monochromatized soft x-rays has been used to study the x-ray lithographic resist properties of poly(cyclohexylmethylsilane-co-dimethylsilane). X-ray absorption spectra near the SiL2,3 edge of unexposed samples were measured to guide the choice of exposure photon energy. We find that poly(cyclohexyl-methylsilane-co-dimethylsilane) exhibits positive tone at x-ray energies near 105 eV (Si 2p resonance), a sensitivity of 1000 mJ/cm2 and a contrast of 1.5. Sensitivity is found to increase markedly when exposed samples are held in air before development. Using simple wire mesh masks, estimates of the minimum achievable linewidth have been made.


2004 ◽  
Author(s):  
Francesco Flora ◽  
Giuseppe Baldacchini ◽  
Francesca Bonfigli ◽  
Antonella Lai ◽  
Tiziana Marolo ◽  
...  

2004 ◽  
Vol 22 (3) ◽  
pp. 323-333 ◽  
Author(s):  
EDMOND TURCU ◽  
RICK ALLOT ◽  
NICOLA LISI ◽  
DIMITRI BATANI ◽  
FULVIA BORTOLOTTO ◽  
...  

An ensemble of new techniques has been developed to study cell metabolism. These include: CO2production monitoring, cell irradiation with soft X rays produced with a laser-plasma source, and study of oscillations in cell metabolic activity via spectral analysis of experimental records. Soft X-rays at about 0.9 keV, with a very low penetration in biological material, were chosen to produce damages at the metabolic level, without great interference with DNA activity. The use of a laser-plasma source allowed a fast deposition of high doses. Monitoring of CO2production allowed us to measure cell metabolic response immediately after irradiation in a continuous and noninvasive way. Also a simple model was developed to calculate X-ray doses delivered to the different cell compartments following a Lambert–Bouguet–Beer law. Results obtained onSaccharomyces cerevisiaeyeast cells in experiments performed at Rutherford Appleton Laboratory are presented.


1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.


Author(s):  
R. H. Duff

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.


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