Law
Enforcement
NIST
Hair ID System May Help Put ‘Locks’ on Criminals
The
hairs found at crime scenes today cannot be matched with certainty
to a specific person. But a forensic technique developed by the
National Institute of Standards and Technology now undergoing
a second formal study—after encouraging initial results—someday
may help identify criminals by chemical components in hair.
While
making environmental measurements in 1993, NIST analytical chemist
Bruce Benner adapted supercritical fluid extraction (a process
similar to one used for decaffeinating coffee) to evaluate hair.
The technique allows the chemical components of hair samples to
be identified with gas chromatography and mass spectrometry equipment
already used in crime labs. The chemicals can be either natural
(such as cholesterol) or artificially deposited (such as shampoo).
A
1999 study using hair samples from 20 people, funded by the National
Institute of Justice through NIST’s Office
of Law Enforcement Standards, found consistent chemical profiles
for individuals. The new study—using FBI and commercially
available hair samples from at least 100 people—will examine
the extent to which the chemical profile of hair resembles a fingerprint
unique to an individual. The work will be performed primarily
by NIST/National Research Council post-doctoral fellow John Goodpaster.
FBI
scientists hope that the new study will prove the NIST technique
provides a faster, more reliable identification-by-hair method
than traditional visual examination and that it may complement
the more recent mitochondrial DNA analysis. Another point of interest
for the FBI is the fact that the NIST technique requires only
very small amounts of hair, thereby leaving plenty of sample for
other forensic tests.
Media
Contact:
Michael
Newman, (301) 975-3025
Fire
Safety
How Fast
Does Fire Spread? See for Yourself in New NIST Video
People
who are experts about fire know that the blazes depicted in
movies and TV give the wrong impression about how fast a fire
can really grow and how much time is truly available for a person
to escape from it. This misinformation may cause people to underestimate
fire dangers and make bad, sometimes tragic, decisions in a
real fire situation.
The National
Institute of Standards and Technology’s Building
and Fire Research Laboratory has assembled a 10-minute collection
of fires on video taken from recent large-scale tests conducted
at the institute. The program clearly portrays how fires grow
in furnished rooms from ignition to flashover (when all combustibles
in a room burst into flames and the fire spreads rapidly). The
video’s segments show the ignition and burning of (1) a
dry Christmas tree in a living room (flashover in 45 seconds),
(2) an upholstered sofa in a living room (flashover in four
minutes) and (3) a wastebasket near an office workstation (flashover
in about five minutes).
The BFRL
flashover video is an extremely effective tool for fire departments,
schools and other organizations to use in safety education programs.
For a free VHS copy, send a request to Nelson Bryner by fax
at (301) 975-4052 or by e-mail to nelson.bryner@nist.gov.
Media
Contact:
John
Blair, (301) 975-4261
Chemistry
NIST
Standard to Help Satellite Correctly ‘See the Light’
A
small
glass disk designed and manufactured by the National Institute
of Standards and Technology soon will be orbiting the Earth aboard
a satellite that will provide unusually detailed data about the
chemical composition and properties of the planet.
Standard
Reference Material 2035, believed to be the first SRM to be used
in space, is a wavelength standard for transmission measurements
in the ultraviolet, visible and near infrared regions of the electromagnetic
spectrum—the portions closely associated with chemical changes.
It will be used to help monitor and validate the performance of
spectral imaging equipment aboard OrbView-4, scheduled for launch
this month. The project is a joint venture of the Air Force Research
Laboratory Space Vehicles Directorate and Orbital Sciences Corp.
of Dulles, Va. The satellite will be operated by an Orbital affiliate,
ORBIMAGE.
Natural
and manmade materials on the Earth’s surface each exhibit
unique signatures of reflected light from the sun, much of which
cannot be captured with either a conventional camera or the human
eye. Using detectors that transform the reflected light into electronic
signals, OrbView-4 will measure the signatures and identify materials
ranging from plant species to minerals to inland and coastal water
features. The resulting imagery has many applications, including
mineral, oil and gas exploration; forestry, farming and environmental
monitoring; and military activities.
SRM
2035 was originally developed for Earth-bound chemical applications
in a narrower spectral range but is well suited for the space
application because of its small size, light weight, broad spectral
coverage and well-characterized temperature dependence.
Media
Contact:
Michael
Newman, (301) 975-3025
EDITOR'S
NOTE: Unfortunately, on Sept. 21, 2001 (after this issue went
to press), OrbView-4's launch vehicle failed to place the craft
into its proper orbit. NIST's SRM 2035 may yet soar high as part
of an upcoming ozone mapping satellite mission.
Environment
Turning
Seaweed into a Scientific Tool
With
500 kilograms of freeze-dried seaweed that originated off the
shores of Ireland, the National Institute of Standards and Technology
plans to help the international community monitor for radioactive
contamination from Russian nuclear submarines that were discarded
in the Arctic Ocean.
Seaweed
is a key oceanic “sink” for long-lived radioactive elements
(such as radium and uranium), but there is currently no Standard
Reference Material for quality control or validation of methods
used in measurements of these elements in seaweed specimens. SRMs
are solids, liquids and gases that NIST has characterized for
specific physical and chemical properties using state-of-the-art
measurement methods. These certified artifacts are used by industry,
academia and governments to establish the quality and reliability
of devices, goods, medical data and scientific results.
NIST
will use its dried seaweed to make an SRM, a benchmark against
which seaweed specimens can be compared by scientists monitoring
for contamination. The dried seaweed will be bottled, sterilized
and sent to experienced laboratories for analysis. NIST then will
use statistical techniques to evaluate the data before certifying
the SRM as containing specified levels of constituents.
Media
Contact:
Michael
Baum, (301) 975-2763
Old
Ticker at NIST Gets a New Lease on Life
Time
may stand still for no man, but the National Institute of Standards
and Technology has helped get it back on its feet.
The
institute commissioned Phillip Hannah, a precision engineer and
master clock maker from Connecticut, to revitalize a historic
clock in NIST’s museum collection of scientific and technological
artifacts in Gaithersburg, Md. The Riefler Clock, a nearly free
pendulum device designed in 1889 by Clemens Riefler, attained
an accuracy of a hundredth of a second a day and became the time
standard in many astronomical observatories. The National Bureau
of Standards (now NIST) purchased the clock in 1904, three years
after the agency was established. It was used for precise time
interval measurement by NBS until 1929.
Hannah
recently disassembled the dormant clock, cleaned all of the pieces
that required it, performed necessary rewiring and then set the
device in working order. He was impressed with the excellent condition
of the clock, since no new parts were needed to achieve the renovation.
NIST
engineer Richard Rhorer
is now regulating the Riefler Clock to improve its accuracy from
a current loss of one second a week to a rate closer to losing
one second per month. By comparison, the NIST-F1 cesium fountain
atomic clock at NIST’s Boulder, Colo., laboratory neither
gains nor loses a second in nearly 20 million years.
Media
Contact:
Michael
Newman, (301) 975-3025
Education
Classroom
Presentation on Cryogenic Magic Available
Teachers
and others who like to visually demonstrate scientific principles
for classes and large groups will be interested in a new paper
and accompanying animated video from the National Institute of
Standards and Technology that details a cryogenics (the science
of cold temperatures) “magic show.” This “how-to”
kit is the latest addition to more than 20 years of NIST outreach
on science and technology to educational organizations.
Several
members of NIST’s Materials Reliability Division have assembled
the step-by-step plan for creating and performing a presentation
that dramatically shows how changing the temperature of materials
changes their size and shape as well. The list of materials that
can be used includes everything from a banana to a superconducting
magnet.
The
authors provide an overview of cryogenics, a description of the
equipment/supplies needed for the “magic show,” an explanation
of the scientific principles behind each experiment, and easy-to-follow
instructions on how to perform each experiment using different
materials.
For
a free copy of “The Magic of Cryogenics,” contact Sarabeth
Harris, NIST, MC 104, Boulder, Colo. 80305-3328; (303) 497-3237;
sarabeth@boulder.nist.gov.
Ask for paper no. 29-01. For more information on the cryogenics
“magic show,” contact Daniel P. Vigliotti, (303) 497-3351,
vigliotti@boulder.nist.gov.
