Dépouillements

Monitoring of corrosion processes in chloride contaminated mortar by electrochemical measurements and X-ray tomography / M. Beck in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 475–479 Titre : Monitoring of corrosion processes in chloride contaminated mortar by electrochemical measurements and X-ray tomography Type de document : texte imprimé Auteurs : M. Beck, Auteur ; J. Goebbels, Auteur ; A. Burkert, Auteur Année de publication : 2010 Article en page(s) : pp. 475–479 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : contaminated  mortar;  electrochemical  measurements;  pitting  corrosion;  X-ray  tomography Résumé : Corrosion of steel reinforcement in concrete exposed to chloride containing environments is a serious problem in civil engineering practice. Electrochemical methods, e.g., potential mapping, provide information whether the steel reinforcement is still passive or depassivation has been initiated. By applying such techniques no information on the type of corrosion, its extent and distribution of corrosion products is available. Particular the corrosion progress is a significant problem. Especially in the case of macrocell corrosion in reinforced concrete structures, the development at the anode cannot be separated into corrosion damage resulting from macrocell corrosion or self-corrosion. Until now also in laboratory tests it is impossible to collect such information without destroying specimens after electrochemical testing was performed. To overcome this problem it was tried to study the steel surface within the mortar specimens by X-ray tomography (CT). Within the scope of these investigations it could be shown, that X-ray tomography is suitable to make corrosion pits and their development visible which are embedded in a mortar with a cover thickness of about 35 mm. In this publication the time-dependent corrosion damage of reinforced steel is documented by X-ray tomography. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905364/abstract [article] Monitoring of corrosion processes in chloride contaminated mortar by electrochemical measurements and X-ray tomography [texte imprimé] / M. Beck, Auteur ; J. Goebbels, Auteur ; A. Burkert, Auteur . - 2010 . - pp. 475–479. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 475–479 Mots-clés : contaminated  mortar;  electrochemical  measurements;  pitting  corrosion;  X-ray  tomography Résumé : Corrosion of steel reinforcement in concrete exposed to chloride containing environments is a serious problem in civil engineering practice. Electrochemical methods, e.g., potential mapping, provide information whether the steel reinforcement is still passive or depassivation has been initiated. By applying such techniques no information on the type of corrosion, its extent and distribution of corrosion products is available. Particular the corrosion progress is a significant problem. Especially in the case of macrocell corrosion in reinforced concrete structures, the development at the anode cannot be separated into corrosion damage resulting from macrocell corrosion or self-corrosion. Until now also in laboratory tests it is impossible to collect such information without destroying specimens after electrochemical testing was performed. To overcome this problem it was tried to study the steel surface within the mortar specimens by X-ray tomography (CT). Within the scope of these investigations it could be shown, that X-ray tomography is suitable to make corrosion pits and their development visible which are embedded in a mortar with a cover thickness of about 35 mm. In this publication the time-dependent corrosion damage of reinforced steel is documented by X-ray tomography. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905364/abstract

Embeddable reference electrodes for corrosion monitoring of reinforced concrete structures / G. S. Duffó in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 480–489 Titre : Embeddable reference electrodes for corrosion monitoring of reinforced concrete structures Type de document : texte imprimé Auteurs : G. S. Duffó, Auteur ; S. B. Farina, Auteur ; C. M. Giordano, Auteur Année de publication : 2010 Article en page(s) : pp. 480–489 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : corrosion;  monitoring;  reference  electrodes;  reinforced  concrete Résumé : Mixed-metal oxide (MMO), graphite and laboratory-made Ag/AgCl electrodes were electrochemically characterized to be used as reference electrodes embedded in concrete structures. Electrodes were studied in both, aqueous solutions of pH ranging from 7 to 13.5 and embedded into cement mortars; and the electrochemical studies were carried out in the absence and presence of chloride ions. Potential evolution, polarisation behaviour, galvanostatic pulse response and impedance characteristics of the electrodes were carried out in aqueous solutions. Besides, the electrochemical stability of the electrodes embedded in mortar was studied for an exposure period of two years. It was found that the MMO pseudo-reference electrode is pH-sensitive, the graphite pseudo-reference electrode is oxygen sensitive and the Ag/AgCl pseudo-reference electrode is chloride sensitive. Then, regarding the corrosion monitoring of steel rebars, care should be taken to avoid misleading interpretations of the corrosion potential measurements. However, any of them can be used to measure the corrosion rate of the rebars by means of traditional electrochemical techniques. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905346/abstract [article] Embeddable reference electrodes for corrosion monitoring of reinforced concrete structures [texte imprimé] / G. S. Duffó, Auteur ; S. B. Farina, Auteur ; C. M. Giordano, Auteur . - 2010 . - pp. 480–489. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 480–489 Mots-clés : corrosion;  monitoring;  reference  electrodes;  reinforced  concrete Résumé : Mixed-metal oxide (MMO), graphite and laboratory-made Ag/AgCl electrodes were electrochemically characterized to be used as reference electrodes embedded in concrete structures. Electrodes were studied in both, aqueous solutions of pH ranging from 7 to 13.5 and embedded into cement mortars; and the electrochemical studies were carried out in the absence and presence of chloride ions. Potential evolution, polarisation behaviour, galvanostatic pulse response and impedance characteristics of the electrodes were carried out in aqueous solutions. Besides, the electrochemical stability of the electrodes embedded in mortar was studied for an exposure period of two years. It was found that the MMO pseudo-reference electrode is pH-sensitive, the graphite pseudo-reference electrode is oxygen sensitive and the Ag/AgCl pseudo-reference electrode is chloride sensitive. Then, regarding the corrosion monitoring of steel rebars, care should be taken to avoid misleading interpretations of the corrosion potential measurements. However, any of them can be used to measure the corrosion rate of the rebars by means of traditional electrochemical techniques. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905346/abstract

Cost effectiveness and application of online monitoring in reinforced concrete structures / Y. Schiegg in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 490–493 Titre : Cost effectiveness and application of online monitoring in reinforced concrete structures Type de document : texte imprimé Auteurs : Y. Schiegg, Auteur ; L. Steiner, Auteur Année de publication : 2010 Article en page(s) : pp. 490–493 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : corrosion  of  steel  in  concrete;  monitoring Résumé : The annual costs for the maintenance of the Swiss national road networks amount to SFr. 560–640 millions 1. Due to the limited means and the large number of engineering structures at the critical age between 30 and 45 years cost-effective solutions for the monitoring and the maintenance of these structures have to be found 2. In this paper the life cycle costs of an engineering structure using a sensor network (online-monitoring system) were investigated. These costs were compared to the costs of classical inspection techniques. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905556/abstract [article] Cost effectiveness and application of online monitoring in reinforced concrete structures [texte imprimé] / Y. Schiegg, Auteur ; L. Steiner, Auteur . - 2010 . - pp. 490–493. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 490–493 Mots-clés : corrosion  of  steel  in  concrete;  monitoring Résumé : The annual costs for the maintenance of the Swiss national road networks amount to SFr. 560–640 millions 1. Due to the limited means and the large number of engineering structures at the critical age between 30 and 45 years cost-effective solutions for the monitoring and the maintenance of these structures have to be found 2. In this paper the life cycle costs of an engineering structure using a sensor network (online-monitoring system) were investigated. These costs were compared to the costs of classical inspection techniques. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905556/abstract

Modelling of reinforcement corrosion – geometrical effects on macrocell corrosion / J. Warkus in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 494–504 Titre : Modelling of reinforcement corrosion – geometrical effects on macrocell corrosion Type de document : texte imprimé Auteurs : J. Warkus, Auteur ; M. Raupach, Auteur Année de publication : 2010 Article en page(s) : pp. 494–504 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : concrete;  corrosion;modelling;  reinforcement;  simulation Résumé : Reinforcement corrosion is still the most frequent reason for damage of concrete structures. It can be caused by carbonation or the ingress of chlorides. In cases of localized contaminations with chlorides, macrocells with very high corrosion rates can be established. Thereby the resulting macrocell current is dependent on many different boundary conditions like driving voltage, concrete resistivity and the geometrical arrangement of anode and cathode. In order to investigate macrocell corrosion, the herein presented research work was carried out by laboratory experiments and additionally by numerical analyses. First the numerical simulations were calibrated by laboratory measurements and thereafter, a numerical parameter study was carried out to increase the available database and identify the impact of changes in single parameters. As the focus is on geometrical effects, all laboratory specimens and numerical models were designed to represent practical conditions with diverse geometrical arrangements, e.g., slabs or beams with localized depassivations. In addition, parameters like concrete resistivity, driving voltage and cathode to anode surface area ratios have been varied. Thereafter, all results were used to derive cell factors for a simple macrocell current estimation. The present status of the project will be presented and discussed. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905437/abstract [article] Modelling of reinforcement corrosion – geometrical effects on macrocell corrosion [texte imprimé] / J. Warkus, Auteur ; M. Raupach, Auteur . - 2010 . - pp. 494–504. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 494–504 Mots-clés : concrete;  corrosion;modelling;  reinforcement;  simulation Résumé : Reinforcement corrosion is still the most frequent reason for damage of concrete structures. It can be caused by carbonation or the ingress of chlorides. In cases of localized contaminations with chlorides, macrocells with very high corrosion rates can be established. Thereby the resulting macrocell current is dependent on many different boundary conditions like driving voltage, concrete resistivity and the geometrical arrangement of anode and cathode. In order to investigate macrocell corrosion, the herein presented research work was carried out by laboratory experiments and additionally by numerical analyses. First the numerical simulations were calibrated by laboratory measurements and thereafter, a numerical parameter study was carried out to increase the available database and identify the impact of changes in single parameters. As the focus is on geometrical effects, all laboratory specimens and numerical models were designed to represent practical conditions with diverse geometrical arrangements, e.g., slabs or beams with localized depassivations. In addition, parameters like concrete resistivity, driving voltage and cathode to anode surface area ratios have been varied. Thereafter, all results were used to derive cell factors for a simple macrocell current estimation. The present status of the project will be presented and discussed. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905437/abstract

Protection of the opposite reinforcement layer of RC-structures by CP – results of numerical simulations / M. Bruns in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 505–511 Titre : Protection of the opposite reinforcement layer of RC-structures by CP – results of numerical simulations Type de document : texte imprimé Auteurs : M. Bruns, Auteur ; M. Raupach, Auteur Année de publication : 2010 Article en page(s) : pp. 505–511 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : cathodic  protection;  concrete  repair;  current  distribution;  numerical  simulation Résumé : If cathodic protection (CP) is applied to reinforced concrete structures the anode is usually attached at the concrete surface closest to the corroding reinforcement in order to minimise voltage and protection current that is required. In specific circumstances an anode installation at the concrete surface next to the corroding reinforcement is not practicable, i.e. due to difficult access. In such cases it would be helpful to know whether it is possible to protect the reinforcement by an anode being installed at the opposite surface of the structural element. The question is: does the second reinforcement layer obtain sufficient current to be effectively protected? Since a general answer to this question is not possible because the distribution of protection current depends on several parameters like the geometry and amount of the reinforcement, concrete resistivity, the polarisation behaviour and geometry of corroding and passive zones, a 3 D-FEM model of the current and potential distribution was developed and its accuracy was verified by laboratory results. This paper presents the model itself as well as the results of parameter studies carried out to show the impact of the reinforcement distribution, the concrete resistivity and the polarisation behaviour of the reinforcement on the current distribution within the reinforcement. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905584/abstract [article] Protection of the opposite reinforcement layer of RC-structures by CP – results of numerical simulations [texte imprimé] / M. Bruns, Auteur ; M. Raupach, Auteur . - 2010 . - pp. 505–511. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 505–511 Mots-clés : cathodic  protection;  concrete  repair;  current  distribution;  numerical  simulation Résumé : If cathodic protection (CP) is applied to reinforced concrete structures the anode is usually attached at the concrete surface closest to the corroding reinforcement in order to minimise voltage and protection current that is required. In specific circumstances an anode installation at the concrete surface next to the corroding reinforcement is not practicable, i.e. due to difficult access. In such cases it would be helpful to know whether it is possible to protect the reinforcement by an anode being installed at the opposite surface of the structural element. The question is: does the second reinforcement layer obtain sufficient current to be effectively protected? Since a general answer to this question is not possible because the distribution of protection current depends on several parameters like the geometry and amount of the reinforcement, concrete resistivity, the polarisation behaviour and geometry of corroding and passive zones, a 3 D-FEM model of the current and potential distribution was developed and its accuracy was verified by laboratory results. This paper presents the model itself as well as the results of parameter studies carried out to show the impact of the reinforcement distribution, the concrete resistivity and the polarisation behaviour of the reinforcement on the current distribution within the reinforcement. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905584/abstract

Investigations on the chloride migration in consequence of cathodic polarisation / T. Eichler in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 512–517 Titre : Investigations on the chloride migration in consequence of cathodic polarisation Type de document : texte imprimé Auteurs : T. Eichler, Auteur ; B. Isecke, Auteur ; G. Wilsch, Auteur Année de publication : 2010 Article en page(s) : pp. 512–517 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : cathodic  protection;  chloride  migration;  FEM-modelling;  high  alkaline  environment;  non-saturated  conditions;  reinforced  concrete Résumé : At the Institute for Building Materials Research (ibac) in Aachen and the Federal Institute for Materials Research and Testing (BAM) in Berlin a joint research project is currently running with the aim to develop a numerical model which describes cathodic protection (CP) of reinforced concrete. Special project focus is the CP of the rear reinforcement layer. The resulting model shall include the impact of chemical alterations at the steel surface and within the adjacent concrete on the polarisation behaviour of reinforcement, which are induced by long-term application of CP. The investigations presented in this paper aim to clarify open aspects on the migration of chloride ions due to small electric fields as applied in CP of steel in reinforced concrete structures. A comparatively new method, laser induced breakdown spectroscopy (LIBS), was applied in order to determine chloride concentration profiles on laboratory specimens as one of several model parameters for a mathematical description of CP of the rear reinforcement of reinforced concrete structures. The paper concerns migration tests using non-saturated specimens under laboratory conditions at constant voltage and the application of the experimental parameters on FEM-calculations. The presented results suggest the conclusion that even comparably small electric fields, as applied in CP of steel in concrete, may lead to significant and sustainable reduction in chloride concentration at the surface of the reinforcement. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905560/abstract [article] Investigations on the chloride migration in consequence of cathodic polarisation [texte imprimé] / T. Eichler, Auteur ; B. Isecke, Auteur ; G. Wilsch, Auteur . - 2010 . - pp. 512–517. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 512–517 Mots-clés : cathodic  protection;  chloride  migration;  FEM-modelling;  high  alkaline  environment;  non-saturated  conditions;  reinforced  concrete Résumé : At the Institute for Building Materials Research (ibac) in Aachen and the Federal Institute for Materials Research and Testing (BAM) in Berlin a joint research project is currently running with the aim to develop a numerical model which describes cathodic protection (CP) of reinforced concrete. Special project focus is the CP of the rear reinforcement layer. The resulting model shall include the impact of chemical alterations at the steel surface and within the adjacent concrete on the polarisation behaviour of reinforcement, which are induced by long-term application of CP. The investigations presented in this paper aim to clarify open aspects on the migration of chloride ions due to small electric fields as applied in CP of steel in reinforced concrete structures. A comparatively new method, laser induced breakdown spectroscopy (LIBS), was applied in order to determine chloride concentration profiles on laboratory specimens as one of several model parameters for a mathematical description of CP of the rear reinforcement of reinforced concrete structures. The paper concerns migration tests using non-saturated specimens under laboratory conditions at constant voltage and the application of the experimental parameters on FEM-calculations. The presented results suggest the conclusion that even comparably small electric fields, as applied in CP of steel in concrete, may lead to significant and sustainable reduction in chloride concentration at the surface of the reinforcement. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905560/abstract

Numerical model of Ca(OH)2 transport in concrete due to electrical currents / T. Koster in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 518–523 Titre : Numerical model of Ca(OH)2 transport in concrete due to electrical currents Type de document : texte imprimé Auteurs : T. Koster, Auteur ; W. Peelen, Auteur ; J. Larbi, Auteur Année de publication : 2010 Article en page(s) : pp. 518–523 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : cathodic  protection;  concrete;  electrodeposition;  model Résumé : A mathematical model is being developed to describe a repair method in concrete, called cathodic protection (CP). The model is in principle also useful to describe electrodeposition in concrete, e.g. the process of re-precipitation of Ca(OH)2 invoked by an electrical current. In CP, the current is sent from an external anode to the reinforcement inside the concrete. This model is implemented using the numerical software package Comsol Multiphysics. The model is based on the Nernst–Planck equations and the electroneutrality condition considering the ionic species Na+, OH− and Ca2+ and the solid Ca(OH)2. The mathematical model makes it possible to predict the location where Ca(OH)2 precipitates when a certain current density is used. This could be of great use for controlled crack repair in concrete and for electrochemical re-alkalisation. This paper presents the qualitative behaviour of dissolution and re-precipitation of Ca(OH)2 in CP. It discusses model calculations and preliminary experimental results. Experiments for a more complete validation of the model are in process. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905443/abstract [article] Numerical model of Ca(OH)2 transport in concrete due to electrical currents [texte imprimé] / T. Koster, Auteur ; W. Peelen, Auteur ; J. Larbi, Auteur . - 2010 . - pp. 518–523. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 518–523 Mots-clés : cathodic  protection;  concrete;  electrodeposition;  model Résumé : A mathematical model is being developed to describe a repair method in concrete, called cathodic protection (CP). The model is in principle also useful to describe electrodeposition in concrete, e.g. the process of re-precipitation of Ca(OH)2 invoked by an electrical current. In CP, the current is sent from an external anode to the reinforcement inside the concrete. This model is implemented using the numerical software package Comsol Multiphysics. The model is based on the Nernst–Planck equations and the electroneutrality condition considering the ionic species Na+, OH− and Ca2+ and the solid Ca(OH)2. The mathematical model makes it possible to predict the location where Ca(OH)2 precipitates when a certain current density is used. This could be of great use for controlled crack repair in concrete and for electrochemical re-alkalisation. This paper presents the qualitative behaviour of dissolution and re-precipitation of Ca(OH)2 in CP. It discusses model calculations and preliminary experimental results. Experiments for a more complete validation of the model are in process. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905443/abstract

Study of microstructure and corrosion kinetic of steel guitar strings in artificial sweat solution / I. Rezic in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 524–529 Titre : Study of microstructure and corrosion kinetic of steel guitar strings in artificial sweat solution Type de document : texte imprimé Auteurs : I. Rezic, Auteur ; L. Curkovic, Auteur ; M. Ujevic, Auteur Année de publication : 2010 Article en page(s) : pp. 524–529 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : corrosion;  metals;  scanning  electron  microscopy Résumé : Corrosion processes of strings on musical instruments occur frequently. Such processes significantly influence sound quality, but also human health because metals may provoke skin allergy. Therefore, in this study the corrosion process of six guitar strings and metal ions release associated with nickel allergy was monitored after immersion in sweat solution for 28 days. Dissolution of metal ions was measured as a function of time, and the changes of the samples after 28 days were studied by SEM/EDS. The results have shown that the amounts of dissolved metal ions in corrosive solution are decreasing in the following order: Fe3+ < Sn2+ < Mn2+ < Si4+ < Ni2+. The corrosion of electric guitar strings in artificial sweat solution was determined by the solubility of samples. The electric guitar strings E6, A5 and D4 corrosion kinetic in artificial sweat followed parabolic rate relation, while g3, h2 and e1 strings followed linear rate relation. After the 4 weeks of monitoring, the quantities of the nickel eluted ions did not exceed the limits prescribed by standard regulations. Therefore, such items do not present a threat to human health. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905368/abstract [article] Study of microstructure and corrosion kinetic of steel guitar strings in artificial sweat solution [texte imprimé] / I. Rezic, Auteur ; L. Curkovic, Auteur ; M. Ujevic, Auteur . - 2010 . - pp. 524–529. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 524–529 Mots-clés : corrosion;  metals;  scanning  electron  microscopy Résumé : Corrosion processes of strings on musical instruments occur frequently. Such processes significantly influence sound quality, but also human health because metals may provoke skin allergy. Therefore, in this study the corrosion process of six guitar strings and metal ions release associated with nickel allergy was monitored after immersion in sweat solution for 28 days. Dissolution of metal ions was measured as a function of time, and the changes of the samples after 28 days were studied by SEM/EDS. The results have shown that the amounts of dissolved metal ions in corrosive solution are decreasing in the following order: Fe3+ < Sn2+ < Mn2+ < Si4+ < Ni2+. The corrosion of electric guitar strings in artificial sweat solution was determined by the solubility of samples. The electric guitar strings E6, A5 and D4 corrosion kinetic in artificial sweat followed parabolic rate relation, while g3, h2 and e1 strings followed linear rate relation. After the 4 weeks of monitoring, the quantities of the nickel eluted ions did not exceed the limits prescribed by standard regulations. Therefore, such items do not present a threat to human health. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905368/abstract

Exemplaires

Bibliothèque Ecole Nationale Polytechnique d'Alger

Accueil

Se connecter

Météo

Adresse