Magnesium

Magnesium has the atomic number 12 and is an alkaline earth metal with the symbol Mg. It is a common element, the eighth-most-abundant element in the Earth's crust and ninth in the known universe as a whole. Magnesium is the fourth-most-common element in the Earth as a whole (behind iron, oxygen and silicon), making up 13% of the planet's mass and a large fraction of the planet's mantle.

The free element (metal) is not found naturally on Earth, as it is highly reactive (though once produced, it is coated in a thin layer of oxide (see passivation), which partly masks this reactivity). The free metal burns with a characteristic brilliant-white light, making it a useful ingredient in flares. You probably remember burning Magnesium Ribbon in school.  Some of the light that burning magnesium produces is in the ultraviolet range. Just as ultraviolet light will burn your skin, it will also burn the retinas of your eyes if they are not protected, hence not looking directly at the light or using suitable safety eyewear.

Since magnesium is less dense than aluminium, these alloys are prized for their relative lightness and strength.

Magnesium has many uses, but most of us are familiar with aluminium-magnesium alloys, which are often found in cell phones and other electronic gadgets that must be strong yet light weight. Gardeners and tropical fish hobbyists are also very familiar with magnesium, since plants need it to grow (a magnesium deficiency is indicated by yellow leaves).  Animals need small amounts of magnesium to support proper bodily functions too.

For more information visit:-
http://en.wikipedia.org/wiki/Magnesium
http://www.theguardian.com/science/punctuated-equilibrium/2011/may/13/1?guni=Article:in%20body%20link

What is a Rotary Evaporator?

A rotary evaporator is a device used in laboratories for the efficient and gentle removal of solvents from samples by evaporation. Scientists often talk about a sample being evaporated under reduced pressure - ie in a rotary evaporator.

Rotary evaporators are also used in molecular cooking for the preparation of distillates and extracts.

 

The main components of a rotary evaporator are:

1. A motor unit that rotates the evaporation flask or vial containing the user's sample.
2. A vapour duct that is the axis for sample rotation, and is a vacuum-tight conduit for the vapour being drawn off of the sample.
3. A vacuum system, to substantially reduce the pressure within the evaporator system.
4. A heated fluid bath (generally water) to heat the sample.
5. A condenser with either a coil passing coolant, or a "cold finger" into which coolant mixtures such as dry ice and acetone are placed.
6. A condensate-collecting flask at the bottom of the condenser, to catch the distilling solvent after it re-condenses.
7. A mechanical or motorised mechanism to quickly lift the evaporation flask from the heating bath.

The vacuum system used with rotary evaporators can be as simple as a water aspirator with a trap immersed in a cold bath (for non-toxic solvents), or as complex as a regulated mechanical vacuum pump with refrigerated trap.

Glassware used in the vapour stream and condenser can be simple or complex, depending upon the goals of the evaporation, and any propensities the dissolved compounds might give to the mixture (e.g., to foam or "bump").

Commercial instruments are available that include the basic features, and various traps are manufactured to insert between the evaporation flask and the vapour duct. Modern equipment often adds features such as digital control of vacuum such as the KNF SC950 unit shown below, digital display of temperature and rotational speed, and vapour temperature sensing.

Users of rotary evaporators must take precautions to avoid contact with rotating parts, particularly entanglement of loose clothing, hair, or necklaces. Under these circumstances, the winding action of the rotating parts can draw the users into the apparatus resulting in breakage of glassware, burns, and chemical exposure. Extra caution must also be applied to operations with air reactive materials, especially when under vacuum. A leak can draw air into the apparatus and a violent reaction can occur.  Care must also be taken to avoid implosions resulting from use of glassware that contains flaws, such as star-cracks. Explosions may occur from concentrating unstable impurities during evaporation.

What would it be like... if you could just disappear from the daily lab routine? As easily and quickly as liquid escapes from the rotary evaporator? This is the fantasy in the IKA image video above.

For more information visit:-
http://en.wikipedia.org/wiki/Rotary_evaporator
https://www.prlabs.co.uk/news/article.php?Id=120
http://www.knf.co.uk/products/laboratory-pumps/product/categories/vacuum-pump-systems/
http://www.ika.com/Products-Lab-Eq/Rotary-Evaporators-Rotary-evaporator-distilling-distillation-cph-35/
http://www.heidolph-instruments.com/products/rotary-evaporators/
http://www.stuart-equipment.com/category.asp?dsl=118&mnu=23

All available through P&R Labpak Limited

The World Cup is fast approaching.....the science of the football

The early forms of football played in England, sometimes referred to as "mob football", would be played between neighbouring towns and villages, involving an unlimited number of players on opposing teams who would clash en masse, struggling to move an item, such as inflated animal's bladder to particular geographical points, such as their opponents' church, with play taking place in the open space between neighbouring parishes.

The 2014 FIFA World Cup will be the 20th FIFA World Cup, that is scheduled to take place in Brazil from 12 June to 13 July 2014.

The first balls were made of natural materials, such as an inflated pig bladder, later put inside a leather cover, which has given rise to the United States slang-term "pigskin". Modern balls are designed by teams of engineers to exacting specifications, with rubber or plastic bladders, and often with plastic covers. Various leagues and games use different balls.

The precise shape and construction of footballs is typically specified as part of the rules and regulations.

Most modern footballs are stitched from 32 panels of waterproofed leather or plastic: 12 regular pentagons and 20 regular hexagons. The 32-panel configuration is the spherical polyhedron corresponding to the truncated icosahedron; it is spherical because the faces bulge from the pressure of the air inside.

The first 32-panel ball was marketed by Select in the 1950s in Denmark. This configuration became common throughout Continental Europe in the 1960s, and was publicised worldwide by the Adidas Telstar, the official ball of the 1970 World Cup.

A truncated icosahedron (left) compared with a football

The familiar 32-panel football design is sometimes referenced to describe the truncated icosahedron Archimedean solid, carbon buckyballs (as below) or the root structure of geodesic domes.

Buckminsterfullerene C₆₀

There are a number of different types of football balls depending on the match and turf including: training footballs, match footballs, professional match footballs, beach footballs, street footballs, indoor footballs, turf balls, futsal footballs and mini/skills footballs.

For more information visit:-
http://en.wikipedia.org/wiki/Football_(ball)
http://www.labnews.co.uk/features/the-science-of-football/
http://www.fifa.com/worldcup/matches/

Titration

Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of an identified analyte. Since volume measurements play a key role in titration, it is also known as volumetric analysis. A reagent, called the titrant or titrator is prepared as a standard solution. A known concentration and volume of titrant reacts with a solution of analyte or titrand to determine concentration.

Titrator set up

 
The word "titration" comes from the Latin word titulus, meaning inscription or title. The French word titre, also from this origin, means rank.
 

There are several reasons why titration is used in laboratories worldwide:

1. Titration is an established analytical technique
2. It is fast
3. It is a very accurate and precise technique
4. A high degree of automation can be implemented
5. Titration offers a good price/performance ratio compared to more sophisticated techniques
6. It can be used by low-skilled and low-trained operators
7. No need for highly specialised chemical knowledge

Karl Fischer titration: A potentiometric method to analyse trace amounts of water in a substance. A sample is dissolved in methanol, and titrated with Karl Fischer reagent. The reagent contains iodine, which reacts proportionally with water. Thus, the water content can be determined by monitoring the potential of excess iodine.

 

Automated titrators follow a defined sequence of operations. This sequence is basically the same for all different models and brands. This sequence is performed and repeated several times until the endpoint or the equivalence point of the titration reaction is reached (titration cycle).

More complex applications require more steps, for example dispensing of an additional reagent for back titration, dilution of the sample, adjustment of the initial pH value, etc. These steps and the corresponding parameters are defined in the titration methods used by the titrator.


P&R Labpak offer a full range of titration equipment and associated consumables and chemicals such as Hydranal^® reagents.

For more information visit:-
http://en.wikipedia.org/wiki/Titration

On this day - April 11th 1970

Apollo 13 was launched on April 11, 1970, at 13:13 CST from the Kennedy Space Centre, Florida.  It was the seventh manned mission in the American Apollo space program and the third intended to land on the Moon. The lunar landing was aborted after an oxygen tank exploded two days later, crippling the Service Module (SM) upon which the Command Module (CM) depended. Despite great hardship caused by limited power, loss of cabin heat, shortage of potable water, and the critical need to jury-rig the carbon dioxide removal system, the crew returned safely to Earth on April 17.

Apollo 13 launches from Kennedy Space Center, April 11, 1970

A film was made regarding the Apollo 13 mission in 1995 directed by Ron Howard who went to great lengths to create a technically accurate movie, employing NASA's technical assistance in astronaut and flight controller training for his cast, and even obtaining permission to film scenes aboard a reduced gravity aircraft for realistic depiction of the "weightlessness" experienced by the astronauts in space.

Three days into the mission, the crew send a live television transmission from Odyssey, but the networks, believing the public now regards lunar missions as routine, decline to carry the broadcast live. Astronaut Swigert is told to perform a standard housekeeping procedure of stirring the two liquid oxygen tanks in the Service Module. When he flips the switch, one tank explodes, emptying its contents into space and sending the craft tumbling. The other tank is soon found to be leaking, prompting Mission Control to abort the Moon landing.

The crew is soon subjected to freezing conditions.  When the carbon dioxide exhaled by the astronauts reaches the Lunar Module's filter capacity and approaches dangerous levels, an engineering team quickly invents a way to make the Command Module's square filters work in the Lunar Module's round receptacles.  The crew eventually get the Odyssey going and make a safe return to earth.

The Apollo 13 Command Module

The Apollo 13 incident gave rise to the famous line 'Houston, We've Got a Problem'.

Further Apollo missions continued which resulted in successful manned landings on the moon.  There are a number of proposed future missions to the moon - most of them robotic or remote missions using rovers.  However the Russians did announce in 2007 their intention to send cosmonauts to the moon by 2025 and establish a permanent robotically operated base there in 2027–2032.

For more information visit:-

http://en.wikipedia.org/wiki/Apollo_13

Kevlar

Kevlar® is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires. Typically it is spun into ropes or fabric sheets that can be used as such or as an ingredient in composite material components.

Kevlar® is a material formed by combining para-phenylenediamine and terephthaloyl chloride. Aromatic polyamide (aramid) threads are the result. They are further refined, by dissolving the threads and spinning them into regular fibres. When woven, Kevlar® forms a strong and flexible material. If layers of the woven Kevlar® are combined with layers of resin, the resulting ‘rigid’ material is light and has twenty times the strength of steel. It is also superior to specialist metal alloys. However, Kevlar® is expensive due to the demands of the manufacturing process and the need for specialist equipment.

Currently, Kevlar® has many applications, ranging from bicycle tires and racing sails to body armor because of its high tensile strength-to-weight ratio; by this measure it is 5 times stronger than steel on an equal weight basis.

Aramid Fibre

Kevlar® is a well-known component of personal armour such as combat helmets, ballistic face masks, and ballistic vests. Other military uses include bulletproof facemasks used by sentries and spall liners used to protect the crews of armoured fighting vehicles.  Emergency Service's protection gear also uses Kevlar® sometimes if it involves high heat (e.g., tackling a fire), and Kevlar® body armour such as vests for police officers.

Bullet Proof vests

 

Kevlar® is used to manufacture gloves, sleeves, jackets, chaps and other articles of clothing designed to protect users from cuts, abrasions and heat. Kevlar® based protective gear is often considerably lighter and thinner than equivalent gear made of more traditional materials.

For more information visit:-

http://en.wikipedia.org/wiki/Kevlar

http://h2g2.com/edited_entry/A791291

http://www.dupont.co.uk/products-and-services/fabrics-fibers-nonwovens/fibers/brands/kevlar.html

http://www.technologystudent.com/joints/kevlar2.html

 

 

 

What is absolute zero?

In theory, absolute zero is the temperature where the particles of matter stop moving. Absolute zero is impossible to achieve, because all particles move, even if it is just a small vibration. Some people have created temperatures very close to absolute zero, but the record temperature was 100 pK (Picokelvin) above absolute zero.  Even getting close to absolute zero is difficult because anything that touches an object being cooled near absolute zero would give heat to the objects. Scientists use lasers to slow atoms when cooling objects to very low temperatures.

The Kelvin and Rankine temperature scales are defined so that absolute zero is 0 kelvins (K) or 0 degrees Rankine (°R). The Celsius and Fahrenheit scales are defined so that absolute zero is −273.15 °C or −459.67 °F.

At this stage the pressure of the particles is zero. If we plot a graph to it, we can see that the temperature of the particles is zero. The temperature cannot go down any further. Also, the particles cannot move in "reverse" either because as the movement of particles is vibration, vibrating in reverse would be nothing but simply vibrating again. The closer the temperature of an object gets to absolute zero, the less resistive the material is to electricity therefore it will conduct electricity almost perfectly, with no measurable resistance.

The Third Law of Thermodynamics says that nothing can ever have a temperature of absolute zero.

The Second Law of Thermodynamics says that all engines that are powered by heat (like car engines and steam train engines) must release waste heat and can not be 100% efficient. This is because the efficiency (percent of energy the engine uses up that is actually used to do the engine's job) is 100%×(1-T_outside/T_inside), which only is 100% if the outside temperature is absolute zero which it can not be. So, an engine can not be 100% efficient, but you can make its efficiency closer to 100% by making the inside temperature hotter and/or the outside temperature colder.

In September 2013, MIT scientists cooled a sodium gas to the lowest temperature ever recorded -- only half-a-billionth of a degree above absolute zero.

Absolute zero is defined to be −273.15°C, or 0 K.

 

For more information visit:-

http://web.mit.edu/newsoffice/2003/cooling.html

http://en.wikipedia.org/wiki/Absolute_zero