Scientific activities

Sampling and Sampler

 

Faculty of Environmental Science and Engeneering

 

FANTANELE str. nr. 30

postal code :           400294
Telefon :        +40264 30 70 30

Fax :               +40264 30 70 32

mail: robert.begy@ubbcluj.ro

 

Project Leader:

Lect. dr. Begy Robert-Csaba

Scientific activities

RADDEL

Radionuclides As tracers of the Anthropic influence on the Danube Delta sedimentary processes

PNII-RU-TE-2012-3-0351

Po-210 determination

 

1. by acid digestion (latching) with HNO3, HCl and H2O2 (it takes approximately 5 days)

•2. by acid latching but just in the presence of HCl and H2O2 (it takes approximately 3 hours)

•3. After that: Spontaneous deposition on Stainless Steel discs

Stainless Steel tube in which is placed a PVC tube

• This will be the sample holder,

• After sampling this is removed and cut horizontally

              An inadequate sediment sampling procedure leads to compaction of the sediment column. During the dating process  the inaccuracy caused by these effects is not negligible. For minimizing the compaction process a new sampler was designed.

Potential systematic uncertainties involved in 210Pb dating

 

The aim of this study is to analyze two potential uncertainties associated with 210Pb measurements, namely the effect of the silicates found in the sediments and the variation of the mass attenuation relative to IAEA 385 standard, which is highly used in relative activity determination methods. In order to achieve this, we have performed an exploratory study on different sediment cores collected from five lakes situated in three different locations in Romania.

 

 

Știol lake

 

Buhăescu lake

 

Muced lake

 

Iacob lake

 

Saint Anne lake

 

Activity of total sediment sample (Bq/kg)

 

57+/-2

 

2727+/-400

 

330+/-29

 

200+/-30

 

50+/-2

 

Activity of silicate content  (Bq/kg)

 

91 (16%)

 

22618 (9%)

 

-

 

609 (30%)

 

 (21%)

 

Act.con. of silic

 

2.digestion type

 

UDL

 

UDL

 

-

 

UDL

 

UDL

 

Degree of Teflon dish contamination  %

 

20

 

46

 

-

 

35

 

22

 

Effect of silicates to  210Pb dating method

 

-2,05%

 

-1,03%

 

-

 

-19%

 

-10%

 

Uncertainities in 210Pb dating method

 

7%

 

12%

 

-

 

5%