“What will happen if a living animal is put into the acoustic field? Will it also be stably levitated?", asked researcher Wenjun Xie, a materials physicist at Northwestern Polytechnical University.
From Live Science:
Xie and his colleagues employed an ultrasound emitter and reflector that generated a sound pressure field between them. The emitter produced roughly 20-millimeter-wavelength sounds, meaning it could in theory levitate objects half that wavelength or less.
After the investigators got the ultrasound field going, they used tweezers to carefully place animals between the emitter and reflector. The scientists found they could float ants, beetles, spiders, ladybugs, bees, tadpoles and fish up to a little more than a third of an inch long in midair. When they levitated the fish and tadpole, the researchers added water to the ultrasound field every minute via syringe.
The levitated ant tried crawling in the air and struggled to escape by rapidly flexing its legs, although it generally failed because its feet find little purchase in the air. The ladybug tried flying away but also failed when the field was too strong to break away from.
The editors at Live Science note that acoustic levitation has been used for many years. Watch a video of a micro-gravity experiment for a NASA-related project done in 1987 by David Deak:
Friday, December 1, 2006
Sunday, November 26, 2006
The Temperature At The Earth's Core
For the first time, scientists have directly measured the amount of heat flowing from the molten metal of Earth's core into a region at the base of the mantle, a process that helps drive both the movement of tectonic plates at the surface and the geodynamo in the core that generates Earth's magnetic field.
The boundary between the core and the mantle lies half-way to the center of the Earth, at a depth of 1,740 miles (2,900 kilometers). Seismologists are able to probe the structure of this region by studying its effects on seismic waves generated by earthquakes. The new temperature measurements were obtained by relating seismic observations to a recently discovered mineral transformation that occurs at the ultrahigh pressures and temperatures prevailing near the core-mantle boundary.
The boundary between the core and the mantle lies half-way to the center of the Earth, at a depth of 1,740 miles (2,900 kilometers). Seismologists are able to probe the structure of this region by studying its effects on seismic waves generated by earthquakes. The new temperature measurements were obtained by relating seismic observations to a recently discovered mineral transformation that occurs at the ultrahigh pressures and temperatures prevailing near the core-mantle boundary.
The temperature at the upper boundary of the lens, where the phase transition from perovskite to postperovskite occurs, is around 2,500 kelvins (4,000° F). At the lower boundary, where the reverse transition occurs, the temperature is around 3,500 kelvins (5,800° F). These two points gave the researchers a temperature gradient from which they calculated the heat flow, or thermal flux: about 80 million watts per square meter. Extrapolating to the entire surface of the core gave a total heat flow of about 13 trillion watts. link
A Post-Perovskite Lens and D'' Heat Flux Beneath the Central Pacific. 2006. T. Lay et al. Science 314: 1272-1276.
Friday, November 24, 2006
Space Voyagers: The Delta Brain by Alex Nino
Legardary comic book artist Alex Nino recently returned to the medium after too-long an absence with a book called God the Dyslexic Dog. I’m not sure what’s it’s about (other than god as a ‘dyslexic dog’—a point made in just about EVERY panel) but anything with his art in it is worth picking up (despite a mess of a colouring and printing job that pretty much obscures Nino’s fine pen line).
Nino’s name may not have a high recognition factor but he got his start in NA in the 70’s as one of many Philipino artist’s picked up by DC when they exponentially expanded their line and needed new talent fast. Nino never had a ‘name’ book, never did a superhero that I know of, doing mostly SF and horror short stories, back-ups, and stories for Eerie, Creepy and the other anthology mags that flourished for a while. His art is best described as early Walt Simonson on hallucinogens filtered through that fluid style of the best of the Philipinos, e.g. Nestor Redondo – who’s short lived book ‘Rima, The Jungle Girl’ is worth picking up from the 5 cent bins for the gorgeous art and Nino’s bizarre SF back-up story (see below). Hurrah for anyone with enough sense to have him drawing stories again.
Nino’s name may not have a high recognition factor but he got his start in NA in the 70’s as one of many Philipino artist’s picked up by DC when they exponentially expanded their line and needed new talent fast. Nino never had a ‘name’ book, never did a superhero that I know of, doing mostly SF and horror short stories, back-ups, and stories for Eerie, Creepy and the other anthology mags that flourished for a while. His art is best described as early Walt Simonson on hallucinogens filtered through that fluid style of the best of the Philipinos, e.g. Nestor Redondo – who’s short lived book ‘Rima, The Jungle Girl’ is worth picking up from the 5 cent bins for the gorgeous art and Nino’s bizarre SF back-up story (see below). Hurrah for anyone with enough sense to have him drawing stories again.
Space Voyagers © DC Comics
CLICK EACH PAGE TO ENLARGE AND READ
CLICK EACH PAGE TO ENLARGE AND READ
Patented This Day: Barbed Wire
In 1874, the first U.S. patent for barbed wire was issued to Joseph F. Glidden of DeKalb, Illinois (No. 157,124). Having filed his application on 27 Oct 1873, Glidden began manufacturing on 1 Nov 1873, in DeKalb. The barbs were cut from sheet metal and were inserted between two wires which were twisted considerably more than with today's common design.
Glidden’s barbed wire opened the plains to large-scale farming, and closed the open range, bringing the era of the cowboy and the round-up to an end. link
Saturday, November 18, 2006
Vaughn Bodé’s 20,000 Leagues Under The Sea: Part 2
Back in the 60’s Vaughn Bodé illustrated a number of classics that had been rewritten for “reading challenged” kids. The books were published by Frank E. Richards and sold exclusively to schools.
Because these books are almost impossible to find at reasonable prices I’ll be posting all the illos from the best book of the bunch, “Jules Verne’s ’20,000 Leagues Under The Sea” in eight installments.
Read: Part 1 Part 2 Part 3 Part 4 Part 5 Part 6 Part 7 Part 8
Friday, November 17, 2006
Born This Day: August Möbius
Nov 17, 1790 – Sept. 26, 1868. Möbius was a German astronomer, mathematician and author. He is best known for his work in analytic geometry and in topology, especially remembered as one of the discoverers of the Möbius strip, which he had discovered in 1858. A Möbius strip is a two-dimensional surface with only one side.
The ‘other’ Möebius
Through The Möebius Strip:
The ‘other’ Möebius
Through The Möebius Strip:
Sold This Day in 1849: The 1st Bowler Hat
In 1849, the first bowler hat was sold by Lock & Co. of St. James's, London, to William Coke of Holkham, Norfolk for twelve shillings. He had placed an order intending for the hat to protect him from low-hanging branches when he was out shooting. On this day, he travelled to London to take delivery, and tested it by putting it on the floor and stamping on it.
It had been made for Lock & Co. by Thomas and William Bowler, felt hat makers on Southwark Bridge Road, London. This accounts for the name by which the hat is now known, although Lock's still refer to the style as a Coke after their first customer who bought it. link
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