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In addition to identifying the pedagogical approaches favoured by teachers in environmental education, the study aims to reveal the impact of the teaching methods and tools used as well as the teaching difficulties encountered on the effectiveness of teachers’ pedagogical action, particularly in the “Scientific Awakening” course. The study concerns a sample of 636 primary school teachers from the urban and rural areas of the Fez-Meknes Regional Academy of Education in Morocco. The data was collected using a 37-item questionnaire covering the following variables: the teaching methods adopted, the preferred pedagogical approaches, the teaching material used, and the teaching difficulties encountered. The study fits under a descriptive correlational design. The most used teaching methods were the teacher-centred oral methods (dialogue and demonstration method) lacking learner-centred activities (working in small groups, discovery method). The least used ones were laboratory experiments and ICT-based demonstrations. The study shows that teachers who use active methods are the most aware of difficulties in teaching environmental issues and were the most capable of effectively solving learning problems and achieving pedagogical objectives. The study shows that Moroccan primary school teachers need in-service training for the adoption of a systemic and interdisciplinary pedagogical approach. In addition, to address the issue of the alarming failure to complete the “Scientific Awakening” program, we recommend continuous training for the benefit of teachers. This training should cover the appropriate active methods to effectively complete this program. Finally, the study underlined the need to solve the problem of the enormous lack of teaching tools. Certainly, this shortage significantly influences the pedagogical action of teachers regardless of the pedagogical methods adopted.

A new one-dimensional coordination polymer [(N2H5)2Co(HPO4)2] was synthesized by slow evaporation method and characterized by means of single-crystal X-ray diffraction, Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). Its catalytic activity was tested using UV–visible absorption measurements. The compound crystallizes in the monoclinic system (S.G: P21/c) with the cell parameters (Å, °): a = 5.3665(3), b = 11.1271(6), c = 7.7017(4), β = 104.843(4), V = 444.55(4) Å3 and Z = 2. The crystal structure, consisting of a linear chain, is made of rings of [CoN2O4] octahedra and [PO3(OH)] tetrahedra sharing vertices via oxygen atoms coordinated to cobalt centers. The rings are linked to chains running along [100] and form thereby polymeric chains that are connected by hydrogen bonds in a three-dimensional arrangement. The FTIR spectroscopy shows the expected bands of hydrazine and phosphate groups. The thermal behavior consists mainly of the loss of hydrazine moieties leading thus to the formation of anhydrous cobalt phosphate. The phosphate complex exhibits efficiency in catalytic oxidation and degradation of methylene blue dye. The ac magnetic susceptibility shows a peak indicating antiferromagnetic order with a Néel temperature of 5.5 K. Fitting the Curie-Weiss equation to the ac magnetic susceptibility above 50 K gives the average Curie-Weiss Constant to be −11.8 K.

La 2-phenyl-4-methyl-4(tetrazol-5-yl)methyl oxazoline 2 est préparée selon une réaction de cycloaddition mettant en jeu le nitrile 1 et l’azoture de soduim dans le toluéne en présence d’un sel d’amine., Journal Marocain de Chimie Hétérocyclique, Vol 5, No 1 (2006)

Crystals of lanthanide ethylenediamine diphos phates Ln2(NH2(CH2)2NH2)(HP2O7)2·4H2O (Ln = Eu (1), Tb (2), Er (2)) have been synthesized and investigated by single crystal X-ray diffractometry (Eu and Tb phases) and by powder X-ray diffractometry (Er phase). The three structures resulted to be isostructural within triclinic space group P-1, with unit cell parameters of a = 6.5050(6) Å; b = 6.9990(2) Å; c = 9.8450(9) Å; ± = 81.548(5)°; ² = 80.631(19)°; ³ = 88.369(9)°; V = 437.44(6) Å3 (1), a = 6.4360(7) Å; b = 6.9480(12) Å; c = 9.816(4) Å; ± = 81.987(19)°; ² = 80.595(16)°; ³ = 88.591(13)°; V = 428.82(19) Å3 (2), a = 6.39658(2) Å; b = 6.86682(2) Å; c = 9.78849(3) Å; ± = 81.6811(4)°; ² = 80.2304(3)°; ³ = 88.3812(3)°; V = 419.255(3) Å3 (3).The three-dimensional network is built up by the repetition of ab-parallel layers of LnO8 polyhedra corner-sharing with (HP2O7) groups; ethylenediamine molecules lie between such layers, acting both as receptors and donors in strong hydrogen bonds which assure the stabilizing of the entire framework.

New ethylenediammonium diphosphates (NH3(CH2)2NH3)2[Me(HP2O7)2·2H2O] [Me = Co (1), Ni (2)] have been synthesized and investigated by single-crystal X-ray diffractometry. The two structures resulted to be isostructural within triclinic space group P-1. The unit-cell parameters are: a = 7.5211(6) Å, b = 7.5574(3) Å, c = 9.7689(7) Å, ± = 103.6(1)°, ² = 111.14(1)°, ³ = 98.04(1)°, V = 486.9(1) Å3 (1) and a = 7.4631(15) Å, b = 7.5274(12) Å, c = 9.743(3) Å, ± = 104.28(2)°, ² = 110.75(2)°, ³ = 97.50(2)°, V = 481.4(2) Å3 (2). The three-dimensional network is built up by discrete Me(HP2O7)2 · 2 H2O moieties, which, via strong O—H … O bonds, form layers parallel to ab plane. Ethylenediammonium groups are located between such layers, stabilizing the framework via N—H … O bonds. The hydrogendiphosphate group presents bent eclipsed conformation, while the Me ion lies on inversion centre. The structural data, as the bent POP configuration, have been confirmed by the Raman and infrared spectra of the title compounds. In particular, the non-coincidence between the infrared and Raman bands supports the centrosymmetric structure of the investigated crystals.

The increase of luminosity foreseen for the Phase-II HL-LHC upgrades calls for new solutions to fight against the expected pile-up effects. One approach is to measure very accurately the time of arrival of the particles with a resolution of a few tens of picoseconds. In addition, a spatial granularity better than a few millimeter will be needed to obtain a fake jet rejection rate acceptable for physics analysis. These goals could be achieved by using the intrinsic benefits of a standard High-Voltage CMOS technology – in conjunction with a high-resistivity detector material – leading to a fast, integrated, rad-hard, fully depleted monolithic active pixel sensor ASIC.

The in vitro antioxidant activity and the total phenolic content (Folin−Ciocalteu method) of three successive extracts of three varieties of Ceratonia siliqua L. leaves ( grafted female, spontaneous female, spontaneous male) grown in Morocco were investigated by using in-vitro antioxidant models including 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay, reducing power and total antioxidant capacity . T he global polyphenols concentration ranged from 0.45 to 2.64 (g/L GAE) in the three categories of the extracts . In each variety, ethyl acetate fraction exhibited the highest antioxidant activity compared to other fractions. Grafted female trees globally showed a higher polyphenols concentration than the spontaneous female and spontaneous male ones. Our results clearly demonstrate that all extracts have antioxidant capacity. Among the categores, the ethyl acetate extracts of carob tree leaves exhibited strong scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) than the diethyl ether and dichloromethane extracts. Carob leaf extracts contain high amounts of polyphenols with strong antiradical, antioxidant capacity and reducing properties which might constitute an important source of natural antioxidants.