Scientific dictionary main page

Scientific dictionary

science park

Table of Elements

Chemical information

Science dictionary

scientific data

site map

Gift Shop

Index (L)








Moment of truth
More than 25 million people died in Europe from the bubonic plague (the black death) in five years, from 1347 to 1352.

A   B   C   D   E   F   G   H   I   J   K   L   M  
N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

back (LD-LF) LG - LJ next page (LK-LN)

LHC Phys.
Known as the Large Hadron Collider, it is a gigantic particle accelerator machine built at CERN and costs about 6.3 billion Euros. As at the year 2007, it is the largest of its kind, capable to produce up to 14 TeV (14 x 1012 eV) of proton-proton collisions. It is hoped that the collisional experiment may generate the Higgs boson (see Higgs mechanism), a previously unobserved particle that is thought to give all particles with mass. It is also hoped that the machine, once fully operational, can be used to discover any new (if any), unexpected particles beyond the Standard Model predictions.

The collider is a 27 km ring tunnel consists of 1232 superconducting magnets that built about 50 to 150 m beneath the Franco-Swiss border. Once the LHC reaches its full potential in around 2008, the high energetic beam it produces will be the highest density that ever produce in a laboratory.

Liebig condenser Chem.
A condenser use in laboratory having a straight glass tube surround by an outer glass jacket through which cooling water is passed from one end of the jacket to the other end. Hot vapor product (such as distillate) when passing through the inner tube subsequently cool and condense and come out as a liquid at the other end. The condenser is named after the German chemist Justus von Liebig (1803-1873).

ligroin Chem.
The petroleum fraction consisting mostly C7 and C8 saturated hydrocarbons, or higher and boiling in the range 60-120C. Commonly used as a laboratory non-polar solvent.

lime water Chem.
See slaked lime.

liming Agri.
Treatment of soil by adding calcium in various forms such as slaked lime, chalk or limestone. This lowers soil acidity and enhances activity of soil bacteria. Liming also improves soil texture and root development while preventing certain plant diseases such as club root. However, over liming may result in too high soil alkalinity and causes nutrient deficiency in plants.

lipophilic Chem.
Substance and molecule that attracted to fat and lipids and does not easily dissolve in water.

liquation Chem.
The separation of mixtures of solids by heating to a temperature at which lower melting point component liqufies and subsequently separates from other solid components.

Lissajous curves (figures) Maths., Phys.
Named after a French mathematician, Jules A. Lissajous (1822-1880). Two oscillatory curves formed by the composition of two sinusoidal waveforms in perpendicular directions:
Lissajous curve

x = a cos(qxt)
y = b cos(qyt + d)

where a, b are the amplitudes and qx, qy are the angular frequencies and d is the phase difference.
The figures are used to compare the frequencies of two sinusoidal voltages by applying them to the plates of a cathode ray tube.

litharge Min., Chem.
A yellow natural mineral form of lead(II) oxide, PbO, with a tetrahedral crystal structure. It is manufactured by heating molten lead in air or as a secondary mineral form, from the oxidation of galena (PbS) ores. If heated below the melting point of litharge, orthorhombic form of lead(II) oxide, massicot, will form instead.

litmus Chem.
A water-soluble dye extract from certain lichens. It turns red under acid conditions and blue under alkaline conditions, occurring over a wide pH range of 4.5 - 8.3. For this reason, litmus is not used in volumetric titration but is commonly used as a rough indicator of acidity and alkalinity. Litmus solution can also be usually soaked on absorbent paper to give litmus paper and usually packaged in the form of either red or blue litmus papers, which do not change colors if the test solution is neutral.

lixiviation Chem.
A separation process by dissolving out one of the constituent from a mixture. For example, a mixture of salt and sand can be separated by adding water into the mixture. The salt that dissolves in the water can be filtered out and subsequently recovered by means of evaporation.

back (LD-LF) LG - LJ next page (LK-LN)

A   B   C   D   E   F   G   H   I   J   K   L   M  
N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

| Copyright | Privacy | Disclaimer | Contact |

2004-2010, all rights reserved.