AbstractThe corrosion behaviour of three commercial nickel-chromium based dental materials was investigated by electrochemical methods in a corroding mixture of sodium chloride, oxalic acid and lactic acid. In order to establish electrochemical parameters of the corrosion process, linear and cyclic polarization curves were plotted. The samples performances in the corroding system were investigated by weight loss, pH and electrical conductivity measurements. The quantitative analysis related with...
Autori: Adrian Cailean, Daniel Mareci, Daniel Sutiman, Mircea Teodor Nechita
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25132

AbstractElectrochemical impedance spectroscopy (EIS) measurements were used to characterize the electrochemical behaviour of the some commercial dental alloys: two PdAg based alloys (Paliag, PaliagMaestro), two NiCr based alloys (Wirolloy, VeraSoft), two CoCr based alloys (Vitallium, VeraPDI) and two CuAl based alloys (Gaudent, NPG+2) in artificial saliva. Impedance spectra were represented in the form of Bode plots and it was fitted using a commercial softwere package called Electrochemistry Po...
Autori: Daniel Mareci, Gina Ungureanu, Julia Claudia Mirza Rosca, Neculai Aelenei, Romeo Chelariu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25143

? Kinetics considerations concerning the oxidative degradation by photo-fenton process of some antibiotics ? Catalytic wet hydrogen peroxide oxidation of 4-chlorophenol over iron-exchanged clays ? Researches on the negative effects assessment (slugging, clogging, ash deposits) developed at the biomass-coal co-firing ? Contribution to the study of the environmental heritage of a former chemical plant ? Impact of chemicals on derivatives with important therapeutic activity in C...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25376

Include urmatoarele articole:• "Waste not, want not" a study of household attitude toward recycling of solid wastes• A kinetic model for the crystal violet mineralization in water by the electro- fenton process• Development of a coagulation/flocculation predictive model for turbidity removal from tehran water treatment plants• Removal of cadmium (II) from aqueous solutions by sphagnum moss peat: Equilibrium study• Environmental sustainability based on fuzzy models• Impact of dust emi...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25207

AbstractBased on the polarization curves and electrochemical impedance spectroscopy (EIS) in the case of three commercial alloys (Wirolloy, NicromalSoft and VeraSoft) maintained in artificial saliva, it was established the type and the intensity of the corrosion process by means of the corrosion currents value. The passivation of all the samples occurred spontaneously at the open circuit potential. The corrosion currents value decrease after the alloys maintenance in the corrosive medium due the...
Autori: Daniel Mareci, Gina Ungureanu, Julia Claudia Mirza Rosca, Neculai Aelenei
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25235

AbstractThe behaviour of three types of steel, with a variable carbon concentration (from 0.20 to 0.40 %) is studied in medium of ethylene glycol - 10 % methanol - 5 % succinic or adipic acid with water concentration varying between 1 % to 5 %. IR spectroscopy, Xray diffraction and chemical analysis were the methods used for corrosion compounds analysis. The weight losses were measured; also the polarization curves were plotted and the corrosion parameters were established. Based on the obtained...
Autori: Daniel Mareci, Daniel Sutiman, Ioan Iordache, Mircea Teodor Nechita
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25240

AbstractThis paper presents experimental and theoretical studies regarding the behavior after heat treatment of an AlCu4Mg1 aluminum alloy with positive effect on corrosion resistance. On the basis of these experiments and the regression data obtained, an analysis regarding the influence of heating parameters on quenching and aging in order to obtain a certain stress was made. Two cases were considered: stress and quenching temperature are fixed and aging temperature was determined; stress and a...
Autori: Adrian Dima, Alina Adriana Minea
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25281

AbstractThe corrosion resistance of three types of low-carbon steels in water-contaminated mixtures of adipic acid and methanol was investigated. The concentration of water in the organic mixture was progressively raised from 1% to 5%, while the carbon concentration in the steel samples varied from 2% to 4%. Infrared spectroscopy (IR) and X-ray diffraction (XRD) were used to investigate the insoluble corrosion products. Based on the weight losses measurements, on the polarization curves and on t...
Autori: Adrian Cailean, Daniel Mareci, Daniel Sutiman, Mircea Teodor Nechita
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25287

Include urmatoarele articole:• Removal of nickel from aqueous solution by Nordmann FIR (ABIES Nordmanniana (STEV.) SPACH SUBSP. Nordmanniana) cones• Determination of heavy metals in extracts and macerates from garden flowers• Biological phosphorus removal in a high performance single reactor • Advanced Cd2+ removal on dispersed TioO2-fly ash • Remediation techniques for contaminated soils• Separation of uranium(vi) from soils by extraction in aqueous PEG (1550) - Na2SO4 - Na2CO3 two-...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25296

AbstractObservations and data regarding the intense corrosion and deposit phenomena of the carbon steel tube bundle of the heat exchanger are presented. The bundle ensures the cooling of the light fraction C1 - C5 from the top of the distillation column which carries out the removal of pentane and smaller derivates into the RC equipment. Chemical and mineralogical analyses confirm the aggressive action of the fluids flowing through the exchanger. Tests have been done in order to replace the carb...
Autori: Ana-Daniela Georgescu, Lucian Georgescu, Maria Apostolescu, Nicolae Apostolescu, Ovidiu Georgescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25333

AbstractThe electrochemical behaviour of Ti6Al4V and Ti6Al4Zr alloys has been evaluated in Ringer's solution at 250C. The effect of the substitution of vanadium in Ti6Al4V alloy has been specifically addressed. The evaluation of the corrosion resistance was carried out through the analysis of the open circuit potential variation with time, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS) tests. Very low current densities were obtained (order of nA/cm2) from t...
Autori: Adrian Cailean, Daniel Mareci, Daniel Sutiman, Igor Creţescu
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25334

Include urmatoarele articole:• Composite membranes with cross-linked matrimid selective layer for gas separation• Determination of organic compounds from different types of coffee by Hplc and Gc-Ecd analysis• An integrated assessment of the suitability of domestic solar still as a viable safe water technology for India• Investigations on the possibility of natural hemp fibers use for Zn(II) ions removal from wastewaters• Removal of acid red 398 dye from aqueous solutions by coagulation...
Autori:
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25340

AbstractTitanium alloys show attractive properties for biomedical applications where the most important factors are biocompatibility, corrosion resistance, low modulus of elasticity, very good strength-to-weight ratio, reasonable formability and osseointegration. The aim of present study was to evaluate the electrochemical behaviour of Ti6Al7Nb alloy in Ringer’s solution of different pH. This evaluation was carried out through the analysis of the potentiodynamic polarization curves, and electr...
Autori: Daniel Mareci, Julia Claudia Mirza Rosca, Marina Garcia Falcon
ISSN: 1843 - 3707
http://www.ecozone.ro/reviste.php?RID=25363

• Photocatalytic properties of titania - fly ash thin films • Study of the viscosity of some biodiesel – diesel oil blends • Aspects refering to technical and leaching properties of the secondary aluminium slags - cement composites • Studies regarding phenol and 4-chlorophenol sorption by surfactant modified zeolites • Cu-Ni nanostructured electrocatalysts obtained by electrocodeposition • Molecularly imprinted poly (vinyl alcohol) films for the selective a...
Autori: http://www.ecozone.ro/reviste.php?RID=25373

• Photocatalytic properties of titania - fly ash thin films • Study of the viscosity of some biodiesel – diesel oil blends • Aspects refering to technical and leaching properties of the secondary aluminium slags - cement composites • Studies regarding phenol and 4-chlorophenol sorption by surfactant modified zeolites • Cu-Ni nanostructured electrocatalysts obtained by electrocodeposition • Molecularly imprinted poly (vinyl alcohol) films for the selective a...
Autori: http://www.ecozone.ro/reviste.php?RID=25374