Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 117 (2002), S. 3180-3189 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Coulomb explosions of benzene induced by an intense femtosecond laser field were investigated by time-of-flight (TOF) mass spectrometry at a laser intensity of 8.0×1016 W cm−2, with a pulse width of 120 fs. The multiply charged ions of Cq+ (q=1–4) and H+ were detected, and their energies were found to be distributed in the range of 0–160 eV. The explosions were concluded to be anisotropic because the kinetic energies of multiply charged carbon ions are highly parallel to the laser electric field. Molecular dynamics simulations, including the effects of tunnel ionization, electron recombination, and the spatial configuration of benzene for laser electric fields, were performed to elucidate the kinetic-energy distributions and the dynamics of exploded benzene ions. The results of the simulations reproduced the essential points of observation concerning the energies and distributions of the ions in the TOF experiments. The simulations suggest that the charge-hopping processes enhance ionization, finally leading to an anisotropic explosion, which events are similar to those found in the case of C60 explosions. Furthermore, our findings have strongly suggested that time evolution of the hopping greatly depends on spatial configuration in the case of planar molecule benzene. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1435-5922
    Keywords: Key words: ulcerative colitis ; rectal cancer ; endoscopic ultrasonography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract: Endoscopic ultrasonography (EUS) was helpful for the diagnosis of rectal cancer associated with ulcerative colitis. The patient was a 38-year-old Japanese man with a 19-year history of relapsing-remitting type ulcerative colitis involving the entire colon. Routine colonoscopy revealed multiple polypoid prominences in the upper portion of the rectum. EUS revealed a hypoechoic mass in the submucosa beneath and around the polypoid lesion on the most oral side. Signet ring cells were found in a biopsy specimen from this lesion. Subtotal colectomy was performed. A depressed lesion was observed around the prominence on the most oral side; histologically, this lesion was poorly differentiated mucinous and signet ring cell carcinoma extending into the subserosa. The polypoid lesion on the most anal side was well differentiated adenocarcinoma, which was limited to the mucosa. Our findings suggest that EUS is helpful for detecting invasive cancer associated with ulcerative colitis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...