The impact of advance organizers in virtual classrooms on the development of integrated science process skills.

Unlike virtual classrooms that have received extensive research attention in both academic and practical contexts because of their ability to improve students' outcomes, the use of advance organizers are still in need for more research to prove their efficacy in fulfilling expected learning outcomes in these virtual classrooms. Hence, the present study aims to identify the impact of using such organizers in virtual classrooms on the development of students' integrated science process skills. The present study was applied to 64 students who were studying for their Master's degree in the vocational education techniques in the "Research Project" course. Participants were randomly divided into two equal experimental groups with 32 students in each. An assessment card of five main domains was used to evaluate students' skills in research procedural definition, identification and control of the research variables, questions and/or hypotheses, procedures and experimentation besides research interpretation of the results. Data analysis showed that the use of advance organizers in virtual classes was of great effect on the development of participants' integrated science process skills because skills of students in the first experimental group were better mastered than the skills of their peers in the second experimental group in accordance with the subskills in the five domains.

The effect of big data technologies usage on social competence.

The learning management system is a digital environment that enables the tracking of learner activities, allowing special forms of data from the academic context to be explored and used to enhance the learning process. This study aims to identify the effect of using big data technology in digital environments on the development of electronic social competence among optimal investment diploma students. An experimental method was used to explore the effect of big data technologies usage on social competence. The sample for this study consisted of (120) students in the Department of Curriculum and Teaching Methods, divided into two equal groups through random selection. The first group studied the course through a digital environment with the use of big data technology, while the second group studied the course through the digital environment without using big data technology. The electronic social competence scale was further utilized as a tool to meet the study's goal. The experimental findings showed that big data technologies in the used digital environment significantly improved the electronic social competence of Optimal Investment Diploma students (personal skills, self-management skills, and academic skills). The results provide significant proof of the advantages of big data technology in social competence studies and development.

Radiolysis-Assisted Direct Growth of Gold-Based Electrocatalysts for Glycerol Oxidation.

The electrocatalytic oxidation of glycerol by metal electrocatalysts is an effective method of low-energy-input hydrogen production in membrane reactors in alkaline conditions. The aim of the present study is to examine the proof of concept for the gamma-radiolysis-assisted direct growth of monometallic gold and bimetallic gold-silver nanostructured particles. We revised the gamma radiolysis procedure to generate free-standing Au and Au-Ag nano- and micro-structured particles onto a gas diffusion electrode by the immersion of the substrate in the reaction mixture. The metal particles were synthesized by radiolysis on a flat carbon paper in the presence of capping agents. We have integrated different methods (SEM, EDX, XPS, XRD, ICP-OES, CV, and EIS) to examine in detail the as-synthesized materials and interrogate their electrocatalytic efficiency for glycerol oxidation under baseline conditions to establish a structure-performance relationship. The developed strategy can be easily extended to the synthesis by radiolysis of other types of ready-to-use metal electrocatalysts as advanced electrode materials for heterogeneous catalysis.

Students' performance in interactive environments: an intelligent model.

Modern approaches in education technology, which make use of advanced resources such as electronic books, infographics, and mobile applications, are progressing to improve education quality and learning levels, especially during the spread of the coronavirus, which resulted in the closure of schools, universities, and all educational facilities. To adapt to new developments, students' performance must be tracked in order to closely monitor all unfavorable barriers that may affect their academic progress. Educational data mining (EDM) is one of the most popular methods for predicting a student's performance. It helps monitoring and improving students' results. Therefore, in the current study, a model has been developed so that students can be informed about the results of the computer networks course in the middle of the second semester and 11 machine algorithms (out of five classes). A questionnaire was used to determine the effectiveness of using infographics for teaching a computer networks course, as the results proved the effectiveness of infographics as a technique for teaching computer networks. The Moodle (Modular Object-Oriented Dynamic Learning Environment) educational platform was used to present the course because of its distinctive characteristics that allow interaction between the student and the teacher, especially during the COVID-19 pandemic. In addition, the different methods of classification in data mining were used to determine the best practices used to predict students' performance using the weka program, where the results proved the effectiveness of the true positive direction of functions, multilayer perceptron, random forest trees, random tree and supplied test set, f-measure algorithms are the best ways to categories.

The role of metacognition in promoting deep learning in MOOCs during COVID-19 pandemic.

In many nations affected by the COVID-19 pandemic, the situation in higher education institutions has changed. During the pandemic, these institutions have introduced numerous e-solutions to continue the process of education. Besides, research has shown many benefits in the last years of MOOCs. Yet, to date there are few studies to explore some individual characteristics, such as learners' metacognitive skills, that might have an impact on learning outcomes in MOOCs. Furthermore, promotion of deep learning is a serious challenge for online courses including MOOCs. Therefore, the purpose of this research was to explore the role of metacognition in promoting deep learning in MOOCs during COVID-19 pandemic. The participants were students at the department of home economics who were all at the seventh academic level. Based on their scores on the metacognition awareness inventory (MAI), they were divided into two experimental groups, i.e. high metacognition students and low metacognition students. A three- aspect assessment card of deep learning namely connecting concepts, creating new concepts, and critical thinking was used to collect data. The results showed that MOOC was more effective in fostering the deep learning aspects of high metacognition skills, and deep learning as a whole. With regard to backward seeking and slow watching events, results showed significant differences in favor of high metacognition students (HMs). Nevertheless, there were no statistically significant differences between students in both groups regarding the pausing event.

A Self-Assembling NHC-Pd-Loaded Calixarene as a Potent Catalyst for the Suzuki-Miyaura Cross-Coupling Reaction in Water.

Nanoformulated calix[8]arenes functionalized with N-heterocyclic carbene (NHC)-palladium complexes were found to be efficient nano-reactors for Suzuki-Miyaura cross-coupling reactions of water soluble iodo- and bromoaryl compounds with cyclic triol arylborates at low temperature in water without any organic co-solvent. Combined with an improved one-step synthesis of triol arylborates from boronic acid, this remarkably efficient new tool provided a variety of 4'-arylated phenylalanines and tyrosines in good yields at low catalyst loading with a wide functional group tolerance.

Gold(i)-silver(i)-calix[8]arene complexes, precursors of bimetallic alloyed Au-Ag nanoparticles.

In this paper, we report the first synthesis and characterisations of bimetallic gold(i)-silver(i) calix[8]arene complexes. We show that the radiolytic reduction of these complexes leads to the formation of small bimetallic nanoparticles with an alloyed structure, as evidenced by XPS, HR-TEM and STEM/HAADF-EDX measurements.

Benzyloxycalix[8]arene: a new valuable support for NHC palladium complexes in C-C Suzuki-Miyaura couplings.

Benzyloxycalix[8]arene supported catalysts bearing N-heterocyclic carbene palladium complexes on each subunit were readily synthesized. Intermediates and catalysts were fully characterized, allowing for a fine control of their structure. X-ray diffraction analysis confirmed the formation of a calix[8]arene bearing eight well-defined NHC palladium complexes. The macrocyclic structure of calix[8]arenes allowed for a scalable and chromatography-free catalyst synthesis under homogeneous conditions, while the catalytic reaction proceeded under heterogeneous conditions, just by changing the nature of the solvent. Indeed, when used as a suspension in ethanol, a high TON and TOF were obtained through a large panel of functionalized brominated substrates in C-C Suzuki-Miyaura couplings, with low metal contamination after simple filtration.

Recent advances in synthesis of P-BH3 compounds.

This chapter is dedicated to the main achievements since 2007 regarding the synthesis of BH3-phosphorus complexes. Among this class of compounds, phosphine-boranes are the most studied derivatives, mainly as valuable surrogates of phosphines, enabling easy handling and purification. In contrast, metal phosphido-boranes have so far only been considered as in situ intermediates in the P-functionalization of secondary phosphine-boranes. Thorough investigations of their structures as well as their chemical properties have recently been reported. Besides phosphine-boranes and their phosphides, new families of phosphorus-BH3 complexes, have emerged as useful precursors of new structures in the asymmetric series. New routes toward optically active phosphinous-acid boranes and their esters were developed and applied to the synthesis of enantiopure P-stereogenic secondary and tertiary phosphine-boranes. The stereoselective synthesis of P-stereogenic aminophosphine-boranes, precursors of a new class of chiral ligands, has been reported. Studies dealing with the synthesis and reactivity of phosphonite-boranes were successfully applied to the development of efficient syntheses of functionalized H-phosphinates, compounds difficult to access by other routes.

Silyl alkynylphosphine-boranes: key precursors of triazolylphosphines via tandem desilylation-click chemistry.

A versatile synthesis of 1,2,3-triazolyl-4-phosphines from the borane complexes of phosphino-alkynes is reported. The efficiency of the procedure relies on the use of readily available silyl-protected alkynylphosphine-boranes, which were subjected to desilylation with TBAF followed by copper-catalyzed azide-alkyne-cycloaddition in one pot. Subsequent treatment with DABCO afforded the targeted triazolylphosphines in high yields. The reported method was applied to the synthesis of the first example of an enantioenriched P-stereogenic triazolylphosphine (98.8% ee).

Neutral copper-phosphido-borane complexes: synthesis, characterization, and use as precatalysts in C(sp)-P bond formation.

Copper-phosphido-borane complexes were synthesized and isolated for the first time. Their structures were experimentally and computationally investigated. They were shown to display catalytic activity in C(sp)-P bond formation.

Towards the limit of atropochiral stability: H-MIOP, an N-heterocyclic carbene precursor and cationic analogue of the H-MOP ligand.

The configurational stability of biaryl motifs is addressed for the 1-naphthyl-N-benzimidazolyl motif substituted by a single diphenylphosphinyl group at the 2-position. The atropoenantiomers of the N-methylated cation H-MIOP, a less sterically locked analogue of the neutral H-MOP ligand, were resolved by enantiospecific cleavage of the N(2)C-P bond of the resolved enantiomers of BIMIONAP. The latter were obtained by enantiospecific N-methylation of the previously resolved enantiomers of neutral BIMINAP. PdCl(2) complexes of the P,C-chelating N-heterocyclic carbene (NHC)-phosphine ligands derived from (R)- and (S)-H-MIOP were prepared by two enantiospecific routes: by N(2)C-P bond cleavage from the (R)- and (S)-BIMIONAP-PdCl(2) complexes, or by simultaneous coordination of the P and C atoms of the in situ generated free NHC-phosphine. The enantiomerization pathways of H-MOP, H-MIOP, and corresponding NHC-phosphine have been investigated at the B3PW91/6-31G(d,p) level of theory. The calculated enantiomerization barriers of H-MOP and H-MIOP in acetonitrile are equal to 176.0 and 146.4 kJ mol(-1), respectively, and are mainly determined by the distortion of the naphthalene and/or benzimidazole motifs in the transition state. Beyond the stability of their optical rotation at room temperature, the respective calculated Oki's racemization temperatures of 334 and 225 °C allowed us to consider both ligands as configurationally stable.

Imidazoliophosphines are true N-heterocyclic carbene (NHC)-phosphenium adducts.

Whereas the external nucleophilic reactivity of α-amidiniophosphines has been previously illustrated by their complexation to transition-metal centers, their internal electrophilic reactivity is herein investigated by using BIMIONAP (BIMIONAP=N-methylated BIMINAP cation, BIMINAP=formal contraction of the acronyms BIMIP=2,2'-bis(diphenylphosphino)-1,1'-bibenzimidazole and BINAP=2,2'-bis(diphenylphosphino)-1,1'-binaphthyl). Reaction of tetraethylammonium chloride with free BIMIONAP is found to induce heterolytic cleavage of the N(2)C-P bond to give chlorodiphenylphosphine and a transient phosphine-N-heterocyclic carbene (NHC) species that is trapped in situ by protonation to the corresponding phosphine-benzimidazolium cation. When the chloride anion reacts with the cationic [Pd(η(2)-BIMIONAP)Cl(2)] complex, the same cleavage occurs and the phosphine-NHC moiety is trapped in the corresponding [PdCl(2)(η(2)-phosphine-NHC)] complex. When the chloride anion reacts with the dicationic [Pd(π-allyl)(η(2)-BIMIONAP)](+) complex, allyldiphenylphosphine is produced, and the [PdCl(η(2)-phosphine-NHC)(PPh(2)CH(2)CH=CH(2))](+) complex is obtained. Reaction of free BIMIONAP with the harder n-butyllithium nucleophile also induces heterolytic cleavage of the N(2)C-P bond, from which the phosphine-NHC moiety is trapped by hydrolysis of the benzimidazole ring or by P,C-sulfurization. Cleavage of a C-P bond with the weak Cl(-) nucleophile to release the reactive NHC moiety (according to the unusual scheme C-P+Cl(-)→C:+Cl-P) is a definite experimental indication of the dative nature of the N(2)C-P bond of amidiniophosphines, which are, therefore, better described as NHC→phosphenium adducts. This interpretation is supported by the calculation, at the DFT level, of a heterolytic dissociation mode of the N(2)C-P bond lower in energy than the homolytic one. A mesomeric description of the NHC→phosphenium entity is also proposed on the basis of electron localization function (ELF) and atoms in molecules (AIM) analyses. Finally ELF and AIM-based Fukui indices, molecular orbitals, and MESP analyses show that the initial attack of Cl(-) takes place at the carbenic atom of BIMIONAP.

Resolution of the atropochiral biminap ligand and applications in asymmetric catalysis.

Enantiomeric resolution of the rac-biminap ligand is achieved through fractional crystallization of four diastereoisomeric palladium complexes involving ortho-metallated enantiomerically pure (R)-dimethyl(1-naphthylethyl)amine as a chiral auxiliary. After decomplexation, the absolute configuration of (R)-biminap and (S)-biminap has been unambiguously attributed by single-crystal X-ray crystallography, and their stereochemical purity is confirmed by measurement of their optical rotation and by re-derivatization with the initial resolving chiral complex. Palladium complexes of biminap are shown to efficiently catalyze Tsuji-Trost allylic substitution of 3-acetoxy-1,3-diphenylpropene by sodium dimethyl malonate. In the asymmetric version using the enantiomerically pure (R)-biminap ligand, significant solvent and anion effects are evident, and an ee up to 90% is obtained.

Atropochiral (C,C)-chelating NHC-ylide ligands: synthesis and resolution of palladium(II) complexes thereof.

Atropochiral NHC-phosphonium ylides based on the naphthyl-benzimidazolyl core are targeted as strongly sigma-donor C,C-chelating ligands of transition metals. The ligand core is shown to act in either a monodentate (through the carbene center) or bidentate (through the carbene and the ylide centers) fashion in seven palladium(ii) complexes obtained by two sequential strategies. In particular, the enantiomerically pure ortho-palladated (S)-dimethyl(1-phenylethyl)amine co-ligand is used as the chiral resolving agent for the separation of diastereoisomeric NHC-ylide complexes by fractional crystallization. Hydrochloric treatment of either diastereoisomer was found to keep intact the two carbon-palladium bonds, while affording the corresponding enantiomeric beta-zwitterionic NHC-ylide palladate complexes. The absolute configuration of the chirally isolated C,C-chelating ligand was finally confirmed by X-ray crystallography.