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Sciences - Laboratories sciences > Geochemistry Lab.
 

Geochemistry lab includes 3 labs of emission spectrometry,geochemistry,inductively plasma that rock samples is entered to 3 labs as powdered or solution.
The sample is placed on electrode and finally measured quantitatively by spectrometer.
The samples are melted and dissolved in the labs of atomic absorption and inductively coupled plasma and is used the got solution and present analysis systems to assign chemical elements scales.

Atomic absorption system with flame of 2100-Perkin Elmer
Atomic absorption spectrometry system with present flame in GSI is made of USA. This system can measure the following elements in detection limit of ppm.
Cu,Zn,Pb,Cr,Co,Mn,Ag,Cd,Bi,Sb,Fe,Ni,Al,Si,Ca,V,Cr,Sr,Zr,Aua

Atomic absorption spectroscopy with graphite furnace of 5100-Perkin Elmer

Application of electronormal atomizers is like furnace on the increase because of very low detection limit.
Basically,all metallic elements with detection limit of about nanogram  are measured by graphite furnace but working by furnace is so more difficult than flame and repeated results is got hardly but has very high sensitivity.
Atomic absorption by hydride production system

The heavy elements of 4&5&6 groups of periodic table can not be measured by atomic absorption system with flame due to gas hydrides formation that isn’t constant in almost high temperatures,so,they organize volatile hydrides along with sodium boron&hydride in acidity medium that metallic atom becomes free in atomizer(quartz  cell)and is accomplished atomic absorption by light absorption of involved lamp.
This method can be used just forTe,Sn,Se,Sb,Ge,Bi,Hg,As elements.Probability of interelement interferences is very low and it isn’t necessary to be used background correction because only a few elements form volatile hydride.Meanwhile,detection limit of the method is to extent of ng/m too that is accomplished on MHS-20 system.
GSI is equipped with Perkiin Elmer 5100 or 2100 system that is installed.
Flame emission system

This system doesn’t have bright source and atoms become aroused in it by flame heat.This system is used in GSI for measurement of following elements in ppm limit:Li,Na,K
Chloridemeter

This system is used for measurement of chlore amount in solutions or powdered samples that have been melted and it can  measure the chlore amount by minimum 5ppm for solutions and 100 ppm for solid samples.The present system in lab,is made of Jenway company of England.
Moreover the mentioned systems in atomic absorption lab,are used tetrasion method for measuring Mo&W,colorimetry method for assignment of B&Mg&Ca amount and precipitation for assignment of sulphate and sulfur amounts.
Emission s
pectrometry lab
The spectrometry is a science that separates and analyzes radiant energy on the basis of wavelength or frequency and studies resulted spectrum in order to get physical and chemical data.
Spectrograph and spectrometer present in GSI is Jarrell-Ash3&4,American.
Spectrometer can measure the elements of Sn,Zn,Ga,B,Cr,V,Ni,Sr,Yb,Y,Sc,Ba,Co,Cu,Be,P,Ti,Ca,K,Na,Al,Si,Mg,Mn,Fe,Pb,In,Ag,Bi in percent limit.Spectrograph can recognize many elements.
Molecular spectroscopy

This method has been planed on the basis of light absorption by molecules and is used in different limits of wavelengths considering type of the molecule that the noted element is in its structure and the wavelength absorbed by that molecule.
Spectrophotometer used by UV-NIR3100 is made of Japan.This machine is used for measurement of following elements(after forming the chromatic complex of the noted element):Ti,Al,Si,P,Mn,Fe.
Ionic chromatography

Ionic chromatography is accounted one of different methods of liquid chromatography with high effectiveness.
In this method is used very small sample(nearly 100micl).The existing system in Knauer lab of GSI is made of Germany.
At present,This system can measure the bellow elements with detection limit of ppm in natural and tap waters and so on: Na,K,Li,Br,No3,No2,Cl,F,Hpo4,So4.
Inductively coupled plasma lab(ICP)

It is a modern type of emission source that is been planed only for liquid samples.
Of course,the sampling system is used for gases and solids too.One of the main benefits of this system is fast multi-element
 analysis.
The measurement of 50 elements or more is possible in simultaneous analysis,based on type of system in a sample by a polychromatic.The repetitive analysis is accomplished by monochromatic.
The existing machine in GSI(Plus JY70)is made of France and can measure the following elements at present:   Mg,Ca,Fe,Al,Si,Sn,Va,Sb,W,Mo,Cd,As,Sr,Ni,Cu,Cr,Co,Be,Bi,Ba,B,Ag,Ti,Mn.