4th EucheMs chemistry congress

Poster Session 2
s1119
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - Analytical Chemistry
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CorroSion BehAvior of Sintered iron PM
PArtS
A. didu 1 , A. SAMide 1 , M. didu 2
1 University of Craiova- Facullty of Exact Sciences, Chemistry,
Craiova, Romania
2 University of Craiova- Facullty of Mecanics, Automotive
Engineering Transport and Industrial Engineering, Craiova,
Romania
This paper presents some preliminary research on corrosion
behavior in acidic pollutant medium for some sintered composite
materials based on iron. This composite material can be used in
carrying car component parts (gear wheels, levers). For testing
we used cylindrical specimens pressed at 200 MPa, 300 MPa and
400 MPa, having the matrix from powder named ANCORSTEEL
1000B, reinforced with alloyed steel yarns
Experimental samples were subjected to chemical and
electrochemical corrosion in aqueous solutions of de H SO 1M
2 4
and HCl 0.5 M, 1 M, 1.5 M, 2 M, 2.5 M. The experimental results
regarding the corrosion rate for electrochemical tests were
represented by Tafel curves, using a potentiostat VOLTALAB 40;
chemical tests were obtained by calculation of gravimetric
parameters and corrosion parameters. Tests showed that material
to analyze is strongly corroded in weak acid environments, as
factors that influence this process being specified: temperature,
porosity of samples (ranging from 15-20%) and concentration of
used solutions. For this reason, this new composite material
cannot be utilized without using anticorrosion protection methods.
Acknowledgement: This work was partially supported by the
strategic grant POSDRU/88/1.5/S/49516, Project ID 59516
(2009), co-financed by the European Social Fund – Investing in
People, within the Sectorial Operational Programme Human
Resources Development 2007-2013.
4 th EucheMs chemistry congress
P - 0 5 1 5
AntioxidAnt ACtivity of wAter extrACtS in 7
SeLeCted herBS
P. diniSová 1 , z. StenCLová 1 , L. CeSLová 1 ,
P. CeSLA 1 , J. fiSCher 1
1 University of Pardubice, Analytical Chemistry, Pardubice,
Czech Republic
Email: petra.dinisova@student.upce.cz
Herbs are used in many domains, including medicine,
nutrition, flavouring, beverages, dyeing, repellents, fragrances,
cosmetics and they are a rich source of polyphenols. Polyphenolic
compounds are commonly found in both edible and inedible
plants, and they have been reported to have multiple biological
effects, including antioxidant activity. Typical phenolics that
possess antioxidant activity are known to be mainly phenolic acids
and flavonoids. Phenolic acids are a major class of phenolic
compounds, widely occurring in the plant kingdom especially in
fruits and vegetables.
Total equivalent antioxidant capacities (TEAC) and phenolic
contents of 7 spices herbs grown in Czech republic were
investigated. The total antioxidant capacity was estimated by the
following methods: ABTS (2,2-azinobis-(3-ethylbenzthiazoline-
-6-sulfonic acid)), DPPH (1,1-diphenyl-2-picrylhydrazyl radical)
and ferric reducing/antioxidant power (FRAP) expressedas
TEAC. The influence of season, location of harvest and treatment
of selected herbs was investigated.
Keywords: phenolic compounds; herbs; antioxidant activity;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc