Passage Two
Los Alamos National Laboratory scientists are using a new technique to see fingerprints on surfaces that typically make them invisible.
The method uses a technology called mini-X-ray fluorescence to detect chemical elements in fingerprints without altering them, said Christopher Worley, a scientist on the project. "The conventional methods are meant to bring out fingerprint patterns with regular light and they have to treat those with powder, which alters them," Worley said. "With this you don't have to alter it or treat it at all. We can determine the elements in a fingerprint and get a pattern at the same time." The technology focuses a tight beam of X-rays on surfaces with fingerprints and creates a computer picture out of those scans. The equipment costs about $175,000.
For big labs, the method could be a great way to bring out prints that can't be seen any other way, said Vahid Majidi, another lab scientist. "The technique fills a unique niche," Majidi said. "These are prints that would otherwise be useless. If you have prints on a dark surface, for example, they really don't develop well using normal techniques. If you have prints from an adolescent or child, the chemicals in the fingertips are different and don't stick around long enough for traditional methods."
The new method might also be able to tell if the person that left them handled certain types of bomb-making materials, said George Havrilla, another lab scientist. "This is a new approach to fingerprint visualization," Havrilla said. "We're lifting prints, but instead of looking at the finger's natural oils and organic residues we're looking at elemental features left behind."
The technology for scanning the prints is widely available. What's new is the method the lab has created to see them which includes computer software and ways of manipulating the machinery, Worley said.
But the technique isn't for everyone. "We've already had some negative comments on it," Havrilla said with a laugh. "One reviewer told us it's just not practical. But the goal of our work was to demonstrate that it was feasible to see these things."
1. Mini X-ray fluorescence is superior to traditional fingerprint detection technique because________.
A. the chemical elements of fingerprints can be changed
B. it can precisely detect the chemical elements of fingerprints
C. the chemical elements in fingerprints remain unchanged in the process of detection.
D. it can present the invisible structures of fingerprints.
2. Besides determining the elements of fingerprints, the new technology ________.
A. can show us what the fingerprints look like via computer
B. can alter the chemical elements of fingerprints
C. can subsequently give the pictures of fingerprints
D. can focus the X-rays beams to detect the underneath part of fingerprints
3. What is the meaning of "The technique fills a unique niche,"?
A. The technique can patch up the disadvantages.
B. The technique is based on a peculiar idea.
C. The technique has nothing to do with the old method
D. The technique is total different in terms of method and theory.
4.Because of ________, we shouldn’t use traditional technique to detect the fingerprints of child.
A. the different characteristics and short existence of prints comparing with adults
B. his hard-to-analyze characteristics
C. the shortage of funds
D. his altered forms
5. From this passage, we can learn that _________.
A. new technology sometimes proved useless.
B. new technology needs practical improvement before it can be accepted
C. the comments on new technology are always negative
D. new technology requires creative ideas.
