P&R Labpak - Everything for your laboratory

P&R Labpak - Everything for your laboratory
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Friday, 26 October 2012

Conversion Units of Volume


English System

To convert
Multiply by
To obtain
cu in.
0.00433
gal
cu in.
0.000579
cu ft
cu in.
0.0000214
cu yd
gal
231
cu in.
gal
0.1337
cu ft
gal
0.00495
cu yd
gal
0.00000307
acre-ft
gal
0.0238
bbl(oil)
gal
0.8327
Imperial gal
cu ft
1,728
cu in.
cu ft
7,48
gal
cu ft
0.0370
cu yd
cu ft
0.0000230
acre-ft
cu yd
46,656
cu in.
cu yd
202
gal
cu yd
27
cu ft
acre-ft
325,800
gal
bbl (oil)
42
gal
Imperial gal
1.2
gal
acre-ft
43,560
cu ft

Metric System

To convert
Multiply by
To obtain
cu cm
0.06102
cu in.
cu cm
0.03381
ft oz
cu meters
35.31
cu ft
cu meters
1.308
cu yd
cu meters
264.2
US gal
liters
61.02
cu in.
liters
0.03531
cu ft
liters
0.2642
US gal
cu in.
16.39
cu cm
cu in.
0.01639
liters
cu ft
0.02832
cu meters
cu ft
28.317
liters
cu yd
0.7646
cu meters
fl oz
29.58
cu cm
US gal
0.003786
cu meters
US gal
3.786
liters

Friday, 19 October 2012

What is Supersonic Flight?


What Is Supersonic Flight?


A speeding bullet
A bullet fired from a gun travels at supersonic speeds. This picture shows a bullet and the air flowing around it. The bullet is traveling at 1.5 times the speed of sound. Image Credit: Andrew Davidhazy/Rochester Institute of TechnologyView Larger Image
Supersonic flight is one of the four speeds of flight. Objects moving at supersonic speeds are going faster than the speed of sound.

The speed of sound is about 768 miles per hour at sea level. That is about four times faster than a racecar.

Supersonic includes speeds up to five times faster than the speed of sound!

The first person to fly an aircraft faster than the speed of sound was Capt. Charles E. "Chuck" Yeager.


What Flies at Supersonic Speeds?

A bullet fired from a gun flies at supersonic speeds. Some military aircraft also fly this fast. The space shuttle flies at supersonic speeds during parts of its mission.

The most famous airplane to fly passengers at supersonic speeds was called the Concorde. The Concorde's fastest speed was more than twice the speed of sound. It could fly people from London, England, to New York in less than 3 1/2 hours. A regular airplane would take twice that long! The Concorde stopped flying in 2003.
An F/A-18 Hornet aircraft flying through a white cloud
An F/A-18 Hornet aircraft speeds up to supersonic speed. The Hornet is flying through an unusual cloud. This kind of cloud sometimes forms as aircraft break the sound barrier. Credit: Ensign John Gay, USS Constellation, U.S. NavyView Larger Image →


Why Does NASA Study Supersonic Flight?

Learning more about supersonic flight helps NASA make better aircraft and spacecraft. When NASA studies supersonic flight, it is studying aeronautics. Aeronautics is the science of flight.


How Does NASA Study Supersonic Flight?

One way NASA learns more about supersonic flight is by testing models of airplanes in wind tunnels.

Wind tunnels are tube-shaped buildings that move air over a vehicle as if it were flying. Flying model airplanes in wind tunnels helps NASA learn how the real aircraft will fly. In wind tunnels, NASA can test new designs for airplanes.

NASA also studies supersonic flight by flying real supersonic aircraft.

Another way NASA learns about it is by using computers. Computers help scientists test what will happen to a plane when it flies.
A computerized simulation of a modified F-15
One way NASA learns about supersonic flight is through computer simulations. Image Credit: NASA


What Is a Sonic Boom?

A sonic boom is a loud noise like thunder. A person on the ground hears a sonic boom when an aircraft flies overhead at supersonic speeds.

The noise is caused by a fast release of air pressure. Air pressure builds up as a plane flies through the air. When the pressure is released, it makes a loud noise. This is similar to when a balloon pops. A pin that pops a balloon releases the air pressure inside the balloon and causes a loud "pop."

NASA is studying and testing things that could be used on aircraft to lessen the noise from sonic booms.


For more information visit the NASA website.

Friday, 12 October 2012

Travelling at the Speed of Sound

RedBullStratos Mission
Felix Baumgartner

Is it really possible for a human being to break the speed of sound in freefall?
If calculations prove to be accurate, and Felix Baumgartner is successful in his attempts to control his position, he will accelerate from standstill to the speed of sound - that's 0 to approximately 690 miles per hour in 40 seconds or less.
What does it mean to "break the speed of sound"?
Breaking the speed of sound refers to catching up with - and surpassing - the speed at which sound waves are produced in the air. The speed of sound is affected by temperature: where the air is colder, sound travels more slowly. At about 100,000 feet above sea level, Felix Baumgartner will need to accelerate to about 690 miles per hour to match the speed of sound, known as Mach 1. Then if he continues to accelerate and surpasses the speed of sound, he'll be "supersonic."
Is there really a sound "barrier"?
No, it's a figure of speech. The concept stems from the mid-20th century, when early high-speed aircraft sometimes experienced extreme instability, and even broke up, as they neared the speed of sound. Today we know that such instability is caused by shock waves that build up in the "transonic" zone - the range of speeds approaching the speed of sound. Sometimes shock waves even collide with each other, a phenomenon known as the "shock-shock interaction," creating results that can be similar to an explosion. Fortunately, the impact of shock waves becomes less severe with higher altitude, because air becomes less dense. And once an object passes through that imaginary "sound barrier" to catch up with and surpass the speed of sound, flight is smooth.
What other hazards will Felix Baumgartner face as he attempts to break the speed of sound?
The list includes temperatures well below freezing, too little oxygen to breathe, the tendency to spin uncontrollably and air pressure so low that without protection blood is said to "boil" with vapor bubbles.
What will protect Felix Baumgartner from these hazards?
Strategies include intensive training to prepare him for possible instability: the team has developed agraduated, multi-stage test program in which he jumps from successively higher outdoor altitudes, as well as a choreographed step-off from the capsule so that he achieves a streamlined position. Equipment is also important: an innovative full-pressure suit and helmet provide oxygen, protection and pressurization, and a special drogue parachute is available for stabilization if necessary.

Why won't Felix reach terminal velocity before he breaks the speed of sound?
Terminal velocity, a concept familiar to skydivers, refers to the point at which a falling object stops accelerating. Drag, or resistance, is one of the key factors causing terminal velocity. Bailing out at a very high altitude, where the air is thin, should enable Felix to break the speed of sound before reaching more dense air that will create drag and eventually result in his terminal velocity. Still, he'll want to streamline his body as quickly as possible to aid his acceleration.
How will we know that Felix has broken the speed of sound?
Equipment in Felix's chest pack will capture and record the necessary data for review by the mission team as well as by the Fédération Aéronautique Internationale world governing body.

What can be learned by breaking the speed of sound in freefall?
The data gathered about the effects of supersonic freefall can provide valuable tools for researchers looking to develop safety procedures for the pilots and astronauts of today and tomorrow -and for future space tourists. Proof that a human can break the speed of sound in freefall could provide support for the development of sub-orbital bailout procedures that currently don't exist. In noting that the Red Bull Stratos team will be capturing as much physiological and environmental data as possible, medical director Jon Clark says: "We try to anticipate as much as we can about supersonic speed, but we really don't know, because nobody has done this before."
 

Red Bull Stratos, a mission to the edge of space, will attempt to transcend human limits that have existed for 50 years. Supported by a team of experts Felix Baumgartner plans to ascend to 120,000 feet in a stratospheric balloon and make a freefall jump rushing toward earth at supersonic speeds before parachuting to the ground. His attempt to dare atmospheric limits holds the potential to provide valuable medical and scientific research data for future pioneers.

Visit http://www.redbullstratos.com/ for more information.
Next expected launch date, weather permitting is Sunday October 14th 2012.

Friday, 5 October 2012

What is Culture Media?


Because microorganisms are so small, sometimes very large colonies of them are necessary for any kind of experimentation or to determine treatment for disease. To get populations big enough to be studied, scientist have to be able to grow them efficiently, and to do that they use culture media. While the culture media used are in liquid or gelatinous form, often culture media are sold and shipped as dehydrated powders so that they can be mixed up as necessary. It is also important for researchers to know what nutrients suspected pathogens need in order to grow them.

When researchers know how to successfully grow pathogens in a growth medium, they can gain insight into how these substances are harmful. As an example, pseudomonas aeruginosa, a pathogen found in cystic fibrosis patients and burn patients express their genes for virulence in conditions of medium or low iron. Therefore, when a culture is done from one of these patients in a low iron culture, growth of the organisms signal that they are present inside a host and can influence the types of treatment a patient receives.

To determine what goes into a dehydrated culture medium, it is necessary to know the nutritional requirements of the cells that are to be cultured. Once these structures are broken down, they are found to be made up of lipids, amino acids, nucleic acids, sugars, and other compounds. Knowing the chemical formulations of these compounds allows scientists to make an accurate estimate of the cell’s nutritional requirements.

Over time, a body of knowledge is created about strains of bacteria or other microorganisms and their nutritional needs. Culture media are fine-tuned for specific applications. Dehydrated culture media are manufactured for convenience of researchers. With dehydrated media, researchers can mix up custom quantities that are tailored to their unique research needs.
P&R Labpak supply a range of media to suit all applications.