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Atomic Test Effects in the Nevada Test Site Region Thirty-one atomic fission weapons, weapon prototypes, or experimental devices were fired in Nevada from January 1951 to January 1955. All were relatively small in explosive power. They ranged from less than one kiloton up to considerably less than 100 kilotons. The forces released by test detonations in Nevada are very small compared to the tremendous forces released by the large fission and hydrogen weapons tested in the Pacific. Despite their relatively low yield, Nevada tests have clearly demonstrated their value to all national atomic weapons programs. Each Nevada test has successfully added to scientific knowledge needed for development and for use of atomic weapons, and needed to strengthen our defense against enemy weapons. Staging of some tests in Nevada, instead of carrying out all of them in the distant Pacific, also resulted in major savings in time, the most important factor, and in manpower, and money. An unusual safety record has been set. Exposure to Flash The Atomic Cloud

Denisova Cave and the Mystery of the mtDNA Phylogenetic Tree « Rokus Blog Nobody expected a great surprise. Genetic testing of the little finger of an early hominin child found in the Siberian Denisova Cave, Kostenki, in the middle of archeological remains pertaining to Upper Paleolithic culture, would almost for sure confirm DNA similar to ours. There was a slim change that the pinky belonged to a Neanderthal from the neighborhood that got lost, but everything pointed at a an unequivocal member of the advanced group of hominins responsible for introducing symbolic art all over the world, the so-called anatomically modern humans (AMH). The collection of personal adornments and artifacts suggestive of symbolic behavior from the Early Upper Paleolithic deposits of Denisova Cave, Altai, is one of the earliest and the most representative of the Upper Paleolithic assemblages from Northern and Central Asia. Humans spend more time gathering around the campfire to celebrate their victory on Nature, only to challenge evolution in an entirely new way. Dr.

Math, Physics, and Engineering Applets Oscillations and Waves Acoustics Signal Processing Electricity and Magnetism: Statics Electrodynamics Quantum Mechanics Linear Algebra Vector Calculus Thermodynamics Miscellaneous Licensing info. Links to other educational sites with math/physics-related information or java applets useful for teaching: And when you get tired of learning, here is some fun stuff: Java Pong Applet a cute little pong game I wrote a while ago. The Large Hadron Collider The Large Hadron Collider (LHC) is the world’s largest and most powerful particle accelerator. It first started up on 10 September 2008, and remains the latest addition to CERN’s accelerator complex. The LHC consists of a 27-kilometre ring of superconducting magnets with a number of accelerating structures to boost the energy of the particles along the way. Inside the accelerator, two high-energy particle beams travel at close to the speed of light before they are made to collide. Thousands of magnets of different varieties and sizes are used to direct the beams around the accelerator. All the controls for the accelerator, its services and technical infrastructure are housed under one roof at the CERN Control Centre. How many kilometres of cables are there on the LHC? Download the LHC guide [PDF] CERN takes safety very seriously. Read about the safety of the LHC Take a virtual tour of the Large Hadron Collider

The Science Creative Quarterly & A DIALOGUE WITH SARAH, AGED 3: IN WHICH IT IS SHOWN THAT IF YOUR DAD IS A CHEMISTRY PROFESSOR, ASKING “WHY” CAN BE DANGEROUS - StumbleUpon SARAH: Daddy, were you in the shower? DAD: Yes, I was in the shower. SARAH: Why? DAD: I was dirty. The shower gets me clean. DAD: Why does the shower get me clean? SARAH: Yes. DAD: Because the water washes the dirt away when I use soap. DAD: Why do I use soap? DAD: Because the soap grabs the dirt and lets the water wash it off. DAD: Why does the soap grab the dirt? DAD: Because soap is a surfactant. DAD: Why is soap a surfactant? DAD: That is an EXCELLENT question. DAD: Why does soap form micelles? DAD: Soap molecules are long chains with a polar, hydrophilic head and a non-polar, hydrophobic tail. SARAH: Aidrofawwic DAD: And can you say ‘hydrophobic’? DAD: Excellent! DAD: Why does it mean that? DAD: It’s Greek! SARAH: Like a monster? DAD: You mean, like being afraid of a monster? DAD: A scary monster, sure. (pause) SARAH: (rolls her eyes) I thought we were talking about soap. DAD: We are talking about soap. (longish pause) DAD: Why do the molecules have a hydrophilic head and a hydrophobic tail?

The Oh-My-God Particle by John Walker January 4, 1994 Fly's Eye The University of Utah operates a cosmic ray detector called the Fly's Eye II, situated at the Dugway Proving Ground about an hour's drive from Salt Lake City. On the night of October 15, 1991, the Fly's Eye detected a proton with an energy of 3.2±0.9×1020 electron volts.[1,2] By comparison, the recently-canceled Superconducting Super Collider (SSC) would have accelerated protons to an energy of 20 TeV, or 2×1013 electron volts—ten million times less. All evidence points to these extremely high energy particles being protons—the nuclei of hydrogen atoms. Microbial Mass First of all, noting that mass and energy are equivalent, we can calculate the rest mass equivalent of a 3×1020 eV particle to be about 5×10−13 grams. How Fast? How fast was it going? where m0 is the particle's rest mass, v is the particle's velocity, and c is the speed of light. And thus, approximately: v = 0.9999999999999999999999951 c Quicktime Warp Factor Oh-My-God—Engage! But How?

Nanotechnology Basics Home > Introduction > Nanotechnology Basics Nanotechnology Basics Last Updated: Friday, 14-Jun-2013 09:28:04 PDT What is Nanotechnology? Coined as "nano-technology" in a 1974 paper by Norio Taniguchi at the University of Tokyo, and encompassing a multitude of rapidly emerging technologies, based upon the scaling down of existing technologies to the next level of precision and miniaturization. Foresight Nanotech Institute Founder K. In the future, "nanotechnology" will likely include building machines and mechanisms with nanoscale dimensions, referred to these days as Molecular Nanotechnology (MNT). Click image for larger version. This image was written using Dip-Pen Nanolithography, and imaged using lateral force microscopy mode of an atomic force microscope. It uses a basic unit of measure called a "nanometer" (abbreviated nm). There are one billion nm's to a meter. Some of the most promising potential of nanotechnology exists due to the laws of quantum physics. "We know it's possible.

String Theorists Squeeze Nine Dimensions Into Three A simulation of the early universe using string theory may explain why space has three observable spatial dimensions instead of nine. The leading mathematical explanation of physics goes beyond modern particle theory by positing tiny bits of vibrating string as the fundamental basis of matter and forces. String theory also requires that the universe have six or more spatial dimensions in addition to the ones observed in everyday life. Explaining how those extra dimensions are hidden is a central challenge for string theorists. “This new paper demonstrates, for the first time, that our 3-D space appears naturally … from the 9-D space that string theory originally has,” says Jun Nishimura of the High Energy Accelerator Research Organization in Tsukuba, Japan. In the simulation, the universe starts off as a tiny blob of strings that is symmetric in nine different dimensions. Applying string theory to the beginning of the universe in this way has long proven difficult.

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