Artificial intelligence to predict inhibition performance of pitting corrosion

This work aims to compare several algorithms for predicting the inhibition performance of localized corrosion. For this more than 400 electrochemical experiments were carried out in a corrosive solution containing an inorganic inhibitor. Pitting potential is used to indicate the performance of the inhibitor/oxidant mixture to prevent pitting corrosion. At the end of the electrochemical program a file containing all the experimental results has been prepared and submitted to several algorithms. Through a training phase each algorithm uses a set of experimental results to adjust its parameters and another set to predict the pitting potential starting from the properties and the chemical composition of the solution. The prediction performance of an algorithm is estimated by the  difference between experimental pitting potential and the calculated one. The order of performance of the algorithms is: GA-ANN > LS-SVM > PSO-ANN > ANN >ANFIS > KNN > RT > KBP > LDA.Key words: Pitting potential, Corrosion inhibitor, Performance prediction, Artificial intelligence

Oestrus induction in primiparous lactating rabbits by a 48 hours mother-litter separation: endocrine and behavioural responses

[EN] Primiparous does express low mating acceptance during lactation and different oestrus induction methods are employed to improve sexual receptivity. The aim of this work was to study the effect of a biostimulation, a 48 h doe-litter separation (DLS), in primiparous lactating rabbits on mating acceptance, external characteristics of the vulva and plasma concentrations of estradiol, testosterone, progesterone and cortisol. Seventy primiparous does from local population were divided on day 1 after kindling into 2 equal groups: control (C, n=35), where does always had free access to the nest-box, and DLS (n=35), where free suckling was adopted, except from day 9 to day 11 post-partum (PP). Litter size was equalised to 6-7 kits. Before mating, blood samples were obtained from 10 does per group on 9th and 11th d post-partum (dpp). The results showed that the DLS treatment improved the mating acceptance on 11th dpp (88.5 vs. 54.2%; P0.05). In contrast, cortisol plasma levels were not affected by the DLS treatment (-12.4 and -14.4% for control and DLS group; P>0.05). At day 11 PP, higher plasma E2 and P4 levels were described in DLS in comparison to C, although no significant difference was found, while plasma testosterone concentrations tended to be higher in DLS (165.5±27.1 vs. 114.9±31.9 pg/mL, for DLS and C, respectively; P=0.075). In summary, the 48 h doe-litter-separation acted as an efficient oestrus inductor in primiparous lactating rabbits. Insemination of biostimulated does must occur after the 1st suckling episode following the separation. This biostimulation method did not modify cortisol secretion of the rabbit doe.This work was supported by the National Research Program (Algeria). The authors wish to thank Dr. Bellazzoug of Algiers Hospital for the hormone assays.Ilès, I.; Benazzoug, Y.; Messili, A.; Boukhari, S.; Boiti, C. (2013). Oestrus induction in primiparous lactating rabbits by a 48 hours mother-litter separation: endocrine and behavioural responses. World Rabbit Science. 21(3):161-168. doi:10.4995/wrs.2013.1248.SWORD16116821

OPTIMIZATION OF LEARNING ALGORITHMS IN THE PREDICTION OF PITTING CORROSION

This work is part of a scientific research program whose objective is to prevent pitting corrosion of an open cooling circuit of a nuclear installation. Various corrosion inhibitors have been studied. The performances of pitting corrosion inhibition were discussed and compared on the basis of several criteria. The experimental data were collected in a large table and subjected to algorithms in order to construct models for predicting corrosion inhibition performance. We used four algorithms: Genetic Algorithm-Artificial Neural Network (GAANN); Least Squares-Support Vector Machine (LS-SVM), K Nearest Neighbors (KNN) and Regression Tree (RT). We optimized the data fraction reserved for learning and we sought to optimize the parameters specific to each algorithm. The efficiency of pitting inhibition increases in the following order: HCO3- < H2PO4- < CO32- < PO4-2 < PO4 3- < SiO3 2- < MoO4 2- < WO4 2-. Our results showed that the order of performance of the algorithms is: RT < KNN < LS-SVM < GA-ANN

Alteration hydrothermale et deformation ductile des roches volcaniques acides associees au gisement sulfure de draa sfar (Jebilet Centrales, Maroc)

The volcanics and volcanoclastic rocks of Draa Sfar (Central Jebilet, Moroccan hercynian belt) are affected by ductile stress and hydrothermal alteration accompanied by a weak degree of metamorphism (greenschist facies). Some N-S oriented shearing zones, affect locally these formations while being the site of an important hydrothermal activity. The consequences of these transformations from a non to slightly- deformed rhyodacite, show that through these ductile shearing zones: (1) the mineralogical assemblage of hydrothermal alteration is essentially formed by chlorite, sericite, quartz and magnetite; (2) the gradual increase of the alteration indexes is accompanied by the destruction of the phenocrists and the recrystallization of the matrix by phyllosilicates and quartz; (3) the progressive transfer of material is more intense in the more deformed zones where the values of Ti, Al and Zr remain constant. These shearing zones played a very important role in the circulation of fluids and the transformation of the rhyodacite of Draa Sfar.Les roches volcaniques et volcanoclastiques de Draa Sfar (Jebilet centrales, Maroc hercynien) sont affect&eacute;es par une d&eacute;formation ductile accompagn&eacute;e d&rsquo;un m&eacute;tamorphisme de faible degr&eacute; (faci&egrave;s schistes verts) et d&rsquo;une alt&eacute;ration hydrothermale. Des zones de cisaillement de direction N-S, ont affect&eacute; localement ces formations tout en &eacute;tant vecteurs d&rsquo;une importante activit&eacute; hydrothermale. Le suivi de ces transformations &agrave; partir de la rhyodacite non ou peu d&eacute;form&eacute;e, montre qu&rsquo;&agrave; travers ces zones de cisaillements ductiles : (1) l&rsquo;assemblage min&eacute;ralogique d&rsquo;alt&eacute;ration hydrothermale est form&eacute; essentiellement de chlorite, de s&eacute;ricite, de quartz et de magn&eacute;tite ; (2) l&rsquo;augmentation graduelle des indices d&rsquo;alt&eacute;ration s&rsquo;exprime par la destruction des ph&eacute;nocristaux au profit d&rsquo;une matrice recristallis&eacute;e en phyllosilicates et quartz ; (3) le transfert progressif de la mati&egrave;re est plus intense dans les zones d&eacute;form&eacute;es o&ugrave; Ti, Al et Zr restent constants. Ces zones de cisaillements ductiles ont jou&eacute; un r&ocirc;le tr&egrave;s important dans la circulation des fluides &agrave; l&rsquo;origine de la transformation en phyllosilicates de la rhyodacite de Draa Sfar

Ecosystemes steppiques(Cas de Brezina– El Bayadh)

Postprint (published version

Contribution a la comprehension de la qualité des sols de la steppe algerienne (Cas du secteur El Bayadh-Brezina, ouest de l'Algerie)

Postprint (published version

Quantitative study on the changes of Karst groundwater level and hydrochemistry in Jinci spring catchment, Shanxi, China

Since Jinci spring ceased to flow on April 30, 1994, it has never been reflowed, which seriously affects the sustainable utilization of karst groundwater. The purpose of this paper is to provide the basis for the reflow of Jinci spring and the sustainable protection for karst groundwater. Based on the long-term monitoring data from 1994 to 2014, this paper accurately quantifies the changes in the quantity and hydrochemistry of karst groundwater resources. By means of the Mann–Kendall trend test method, this paper analyzes the variation trends of karst groundwater level, EC, and SO42− in Jinci spring catchment. Monitoring data show that the groundwater level in the karst aquifer declined by 2.32 m from 1994 to 2008, which is equivalent to a loss of 3.3 Mm3 in aquifer storage, while the groundwater level rose by 17.67 m from 2009 to 2014, which constitutes a gain of 25.2 Mm3. The results indicate that (1) karst groundwater level showed a rising trend, which was mainly controlled by the rainfall, exploitation of karst groundwater, and the Fenhe River leakage; (2) groundwater salinity varied greatly and showed an increasing trend: increasing order of 47.83% for the six major ions, 37.52% for EC, and 3.34% for pH; (3) the increase of groundwater salinity is governed by the increase in rainfall salinity, the increase in groundwater runoff time, the recharge of the Fenhe River to groundwater, the increase of sewage in spring catchment, and the ease of solubility of carbonate rocks. The results of this study are of great significance for predicting the groundwater level and salinity of karst aquifer and ensuring the safety of drinking water in Jinci spring catchmen

Quadrupole and octupole collectivity in the semi-magic nucleus 80206Hg126

The first low-energy Coulomb-excitation measurement of the radioactive, semi-magic, two proton-hole nucleus 206Hg, was performed at CERN's recently-commissioned HIE-ISOLDE facility. Two γ rays depopulating low-lying states in 206Hg were observed. From the data, a reduced transition strength B(E2;21+→01+)=4.4(6) W.u. was determined, the first such value for an N=126 nucleus south of 208Pb, which is found to be slightly lower than that predicted by shell-model calculations. In addition, a collective octupole state was identified at an excitation energy of 2705 keV, for which a reduced B(E3) transition probability of 30−13+10 W.u. was extracted. These results are crucial for understanding both quadrupole and octupole collectivity in the vicinity of the heaviest doubly-magic nucleus 208Pb, and for benchmarking a number of theoretical approaches in this key region. This is of particular importance given the paucity of data on transition strengths in this region, which could be used, in principle, to test calculations relevant to the astrophysical r-process