What is a wind tunnel? Simply put, a wind tunnel is a tube or tunnel through which air is blown. What are they used for? A wind tunnel is used to simulate flight conditions or to study how air moves around an aircraft or part of an aircraft. This is immensely safer than testing a new design in flight.
The site, Parts of a Wind Tunnel, shows the five major parts of a wind tunnel - the settling chamber, contraction cone, test section, diffuser and drive section. The settling chamber evens out the airflow. The contraction cone reduces the volume of the airflow and increases its speed. The object being tested, whether is be a whole airplane or just a part, is placed in the test section. The diffuser then slows the air down. The drive section, which may simply be a large fan, is the power that drives that air through the tunnel. If the reader would like to make their own wind tunnel, there are many web sites with instructions. Make a simple wind tunnel gives directions for making one from a furnace pipe and egg cartons. Another site for making a wind tunnel is Wind Tunnel , a NASA sites.
The first wind tunnel dates back to the mid-1700. Initially, an apparatus called a "whirling arm" was used. Objects were attached to the end of the arm and then the arm was spun. It wasn't until approximately 1871 that Frank H. Wenham constructed the first wind tunnel. To see how the whirling arm and the wind tunnel figure into the chronicles of flight, take a look at a timeline of the history of flight. Interestingly, the Wright Brothers used a wind tunnel. Their wind tunnel looks quite primitive by today's standards. This can be seen by comparing the Wright Brothers' wind tunnel with the wind tunnels used by NASA. But they were able to use it to obtain the correct aerodynamic data, which enabled them to fly. If one would like to get an idea of what it was like to use the Wright Brothers' tunnel, the site Interactive Wright 1901 Wind Tunnel is an Java applet that simulates its operation. The site Java Virtual Wind Tunnel simulates a modern day wind tunnel.
Wednesday, June 21, 2006
Monday, June 19, 2006
Blood
He accidentally cut his finger and it bled. Blood. Some people faint at the sight of it. If anyone is feeling queasy, perhaps they should consider moving on to the next blog for blood is the topic of this post.
An excellent and comprehensive site to start learning about blood is PBS's Red Gold, the epic story of blood . One will learn about the basics of blood (what blood is made of; how it's made; its function) and about the history of blood. A blood history timeline tracks scientific development in the understanding and use of blood from approximately 2500 BCE to the present. There is a discussion of blood practices such as bloodletting, using leeches and transfusions and a section on major innovators and pioneers in the field of blood. To round it all out, there are lesson plans suitable to be used in the classroom. The PBS site has a short article on blood groups and blood typing. If anyone is interested in blood types and genetics, a good site to visit is the Blood Type Tutorial by the University of Arizona.
Blood type is determined, in part, by the ABO blood group antigens present on red blood cells
Is anyone looking to have some fun? The site Blood Groups, Blood Typing and Blood Transfusions , part of the Nobel e-museum, is just the ticket. First, one should read through the article (to become familiar with the nomenclature), then proceed onto the game. In the blood typing game*, three patients need transfusions. It is the reader's job to determine their blood type and give them the correct blood. Good luck. (Just as an aside, the Nobel e-museum site is a great site. It is fun and educational with great labs.)
After one's successful stint in ER, perhaps a visit to the The Pfizer Foundation Biochemistry Discovery Lab ** is in order. This interactive lab seeks to discover what molecules are found in scabs. Doing an experiment online is great; no mess; no mistakes and the right result every time. One learns that the fibrinogen molecule in blood react with the thrombin molecule (made after a cut happens) to form fibrin which clump together and form a clot.
The site, Cells Alive! , has a scanning electron micrograph of a blood clot. There is also a scanning electron micrograph of red blood cells. The site hosts an animation that compares the size of a red blood cell to a human hair, dust mite, pollen grain and certain bacteria and viruses. The reader might like to check out Anatomy of a splinter to see white blood cells in action.
I never knew blood was so interesting and fun. And I didn't faint.
*needs flash plug-in
**needs Shockwave plug-in
An excellent and comprehensive site to start learning about blood is PBS's Red Gold, the epic story of blood . One will learn about the basics of blood (what blood is made of; how it's made; its function) and about the history of blood. A blood history timeline tracks scientific development in the understanding and use of blood from approximately 2500 BCE to the present. There is a discussion of blood practices such as bloodletting, using leeches and transfusions and a section on major innovators and pioneers in the field of blood. To round it all out, there are lesson plans suitable to be used in the classroom. The PBS site has a short article on blood groups and blood typing. If anyone is interested in blood types and genetics, a good site to visit is the Blood Type Tutorial by the University of Arizona.
Blood type is determined, in part, by the ABO blood group antigens present on red blood cells
Is anyone looking to have some fun? The site Blood Groups, Blood Typing and Blood Transfusions , part of the Nobel e-museum, is just the ticket. First, one should read through the article (to become familiar with the nomenclature), then proceed onto the game. In the blood typing game*, three patients need transfusions. It is the reader's job to determine their blood type and give them the correct blood. Good luck. (Just as an aside, the Nobel e-museum site is a great site. It is fun and educational with great labs.)
After one's successful stint in ER, perhaps a visit to the The Pfizer Foundation Biochemistry Discovery Lab ** is in order. This interactive lab seeks to discover what molecules are found in scabs. Doing an experiment online is great; no mess; no mistakes and the right result every time. One learns that the fibrinogen molecule in blood react with the thrombin molecule (made after a cut happens) to form fibrin which clump together and form a clot.
The site, Cells Alive! , has a scanning electron micrograph of a blood clot. There is also a scanning electron micrograph of red blood cells. The site hosts an animation that compares the size of a red blood cell to a human hair, dust mite, pollen grain and certain bacteria and viruses. The reader might like to check out Anatomy of a splinter to see white blood cells in action.
I never knew blood was so interesting and fun. And I didn't faint.
*needs flash plug-in
**needs Shockwave plug-in
Friday, June 09, 2006
Bats
Bats are often maligned and feared. But, as we will see, we have nothing to fear from bats. Join us as we learn more about this amazing critter.
Big eared townsend fledermaus bat.
First stop Batworld . This site has many interesting facts about bats. We learn that bats are not blind and are actually mammals. Unfortunately, they are also an endangered species. Are bats useful? Quoting from the site..."Bats are vital to the ecosystem! Fruit bats bring us over 450 commercial products, including 80 medicines. The seed dispersal and pollination activities of fruit and nectar eating bats are vital to the survival of rain forests. Seeds dropped by tropical bats account for up to 95% of forest regrowth on cleared land. Night blooming plants and trees depend on nectar eating bats for pollination. An excellent example is the baobab tree of eastern Africa that is so important to the survival of other kinds of wildlife it is referred to as the "Tree of Life". "Bats in the US eat millions of tons of insects annually"”….. Even their droppings are useful. Bat or bird droppings or feces are called guano. Guano has been used for many years as fertilizer. Scientists are now able to extract enzymes from bacteria, which live only in guano, in order to make laundry detergents and other valuable products. Batworld tells us what to do if we find a bat either indoors or out, how to become a bat rehabilitator and help injured or orphan bats return to the wild and runs a wild sanctuary for bats in Mineral Texas. It is a non-profit organization working to save bats and educate one and all about this beautiful and gentle creature.
Bat Conservation International is a non-profit organization dedicated to the protection of bats and the restoration of bats and their habitat worldwide. This site is everything we want to know about bats and more. It has a bat trivia page as well as a bat FAQ. The species list allows us to identify bats that live in our area. There are beautiful pictures of bats throughout the site. There is an explanation of echolocation or biosonar - how bats see in the dark by emitting a high frequency sound or ultrasound. Here, we can read about rabies in bats and find out if we are in danger. Information is provided for joining the organization and help with their efforts to save the bats.
The site Vampire bats , aimed at kids, has pictures with fun facts. It seems that vampire bats don't drink human blood (they dislike it) but prefer blood from cows, pigs or sheep. There is an anticoagulant in the vampire's saliva which causes the blood to flow without clotting, allowing the bat to lick the blood rather then suck it. The anticoagulant from vampire bats' saliva has been synthesized and is now used in medication for human heart patients (bat saliva potential new treatment for stroke victims). But these bats can carry rabies that can be transmitted to humans.
How can we attract bats to our garden (what plants to grow) (or bats in the garden or gardening for bats)?
Bats for Kids is a great web site to learn about bats. This web site was created for kids with the hope that they…”will like, respect and help protect these endangered species"…. We learn where bats live; what they look like; how they help humans and what they eat-all written in kid friendly language.
A great interactive educational NASA site about bats is aimed at kids in grades 5-8. The site features the adventures of Echo the Bat. Echo learns to fly and becomes separated from his mother. The site challenges kids to use remote sensing (interpretation of satellite images) and biodiversity (a variety of living things in a habitat-a place where a plant or animal naturally or normally lives and grows) to locate Echo as he searches for his mother and other bats.
Lastly, an anecdote about a farmer and how he found out that bats were really his friends.
Big eared townsend fledermaus bat.
First stop Batworld . This site has many interesting facts about bats. We learn that bats are not blind and are actually mammals. Unfortunately, they are also an endangered species. Are bats useful? Quoting from the site..."Bats are vital to the ecosystem! Fruit bats bring us over 450 commercial products, including 80 medicines. The seed dispersal and pollination activities of fruit and nectar eating bats are vital to the survival of rain forests. Seeds dropped by tropical bats account for up to 95% of forest regrowth on cleared land. Night blooming plants and trees depend on nectar eating bats for pollination. An excellent example is the baobab tree of eastern Africa that is so important to the survival of other kinds of wildlife it is referred to as the "Tree of Life". "Bats in the US eat millions of tons of insects annually"”….. Even their droppings are useful. Bat or bird droppings or feces are called guano. Guano has been used for many years as fertilizer. Scientists are now able to extract enzymes from bacteria, which live only in guano, in order to make laundry detergents and other valuable products. Batworld tells us what to do if we find a bat either indoors or out, how to become a bat rehabilitator and help injured or orphan bats return to the wild and runs a wild sanctuary for bats in Mineral Texas. It is a non-profit organization working to save bats and educate one and all about this beautiful and gentle creature.
Bat Conservation International is a non-profit organization dedicated to the protection of bats and the restoration of bats and their habitat worldwide. This site is everything we want to know about bats and more. It has a bat trivia page as well as a bat FAQ. The species list allows us to identify bats that live in our area. There are beautiful pictures of bats throughout the site. There is an explanation of echolocation or biosonar - how bats see in the dark by emitting a high frequency sound or ultrasound. Here, we can read about rabies in bats and find out if we are in danger. Information is provided for joining the organization and help with their efforts to save the bats.
The site Vampire bats , aimed at kids, has pictures with fun facts. It seems that vampire bats don't drink human blood (they dislike it) but prefer blood from cows, pigs or sheep. There is an anticoagulant in the vampire's saliva which causes the blood to flow without clotting, allowing the bat to lick the blood rather then suck it. The anticoagulant from vampire bats' saliva has been synthesized and is now used in medication for human heart patients (bat saliva potential new treatment for stroke victims). But these bats can carry rabies that can be transmitted to humans.
How can we attract bats to our garden (what plants to grow) (or bats in the garden or gardening for bats)?
Bats for Kids is a great web site to learn about bats. This web site was created for kids with the hope that they…”will like, respect and help protect these endangered species"…. We learn where bats live; what they look like; how they help humans and what they eat-all written in kid friendly language.
A great interactive educational NASA site about bats is aimed at kids in grades 5-8. The site features the adventures of Echo the Bat. Echo learns to fly and becomes separated from his mother. The site challenges kids to use remote sensing (interpretation of satellite images) and biodiversity (a variety of living things in a habitat-a place where a plant or animal naturally or normally lives and grows) to locate Echo as he searches for his mother and other bats.
Lastly, an anecdote about a farmer and how he found out that bats were really his friends.
Friday, June 02, 2006
Bose-Einstein Condensate
In 2001 the Nobel Prize in Physics went to two scientists, Eric Cornell of the National Institute of Standards and Technology and Carl Wieman at Colorado University, who were the first to achieve a Bose-Einstein condensate (BEC) in neutral atoms (The 2001 Nobel Prize in Physics ).
I am definitely not a physics person and Bose-Einstein condensate sounds like something I will never understand. But, believe it or not, there are some very readable sites on the Internet on this topic.
One of those sites is the University of Colorado's BCE Homepage. First off, we learn that the Bose-Einstein condensate is a new state of matter (a fifth state, the other four being gas, liquid, solid and plasma). Wonder how many more states of matter are out there waiting to be discovered. It was predicted in 1924 by A. Einstein and S. Bose but not created until 1995. The condensate requires ultra-cold temperatures to form. Wieman and Cornell first formed the condensate at 200-billionths of a degree Celsius above absolute zero. Interestingly, this page states that the coldest place in nature is the depth of outer space, which has a temperature of three degrees above absolute zero. That is why it is believed that the BEC doesn't occur naturally, since colder temperatures are needed for its formation. The University of Colorado site then goes on to explain what exactly a BEC is and how it was made. The discussion is an entertaining exchange between a student and a professor with helpful and fun animations to help with the understanding of the concept being considered. It is a very readable account.
The Bose-Einstein Condensate is Eric A. Cornell's and Carl E. Wieman's own story of how they went about forming the condensate. It was originally published in Scientific American in 1998.
What uses might the condensate be put to, one wonders? So far, it is too early to tell but remember, it took time before the full potential of the laser was realized. The site Bose-Einstein Condensate states that even if it turns out that the condensates have no important practical applications "...they have an important place in science for its own sake. They offer a clearer window than we have ever had before onto the weird world of quantum statistical mechanics. And quantum statistical mechanics is the deepest theory that present human science possesses: it underlies everything...."
I am definitely not a physics person and Bose-Einstein condensate sounds like something I will never understand. But, believe it or not, there are some very readable sites on the Internet on this topic.
One of those sites is the University of Colorado's BCE Homepage. First off, we learn that the Bose-Einstein condensate is a new state of matter (a fifth state, the other four being gas, liquid, solid and plasma). Wonder how many more states of matter are out there waiting to be discovered. It was predicted in 1924 by A. Einstein and S. Bose but not created until 1995. The condensate requires ultra-cold temperatures to form. Wieman and Cornell first formed the condensate at 200-billionths of a degree Celsius above absolute zero. Interestingly, this page states that the coldest place in nature is the depth of outer space, which has a temperature of three degrees above absolute zero. That is why it is believed that the BEC doesn't occur naturally, since colder temperatures are needed for its formation. The University of Colorado site then goes on to explain what exactly a BEC is and how it was made. The discussion is an entertaining exchange between a student and a professor with helpful and fun animations to help with the understanding of the concept being considered. It is a very readable account.
The Bose-Einstein Condensate is Eric A. Cornell's and Carl E. Wieman's own story of how they went about forming the condensate. It was originally published in Scientific American in 1998.
What uses might the condensate be put to, one wonders? So far, it is too early to tell but remember, it took time before the full potential of the laser was realized. The site Bose-Einstein Condensate states that even if it turns out that the condensates have no important practical applications "...they have an important place in science for its own sake. They offer a clearer window than we have ever had before onto the weird world of quantum statistical mechanics. And quantum statistical mechanics is the deepest theory that present human science possesses: it underlies everything...."
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