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This systematic review, specifically a Meta-synthesis, aimed to synthesize the challenges and implementation of Inclusive Education (IE) in selected Asian countries. Fifteen (15) out of 792 studies were selected and screened through a set of inclusion and exclusion criteria. Academic databases such as Google Scholar, Cross Ref, Open Alex, and Scopus using Publish or Perish, and repositories such as The National University of Malaysia Journal Article Repository and Seoul National University Open Repository were used to gather relevant articles. The articles selected were organized using the PRISMA 2020 Flow Diagram. The synthesized data were analyzed using Braun and Clarke's six-step thematic analysis, which emerged with eight sub-themes: insufficient resources, lack of purposeful training and professional development, contrasting IE laws and policies, weak government support, appropriate curriculum and proper classroom organization, assessment practices, awareness of IE, and constant collaboration among different stakeholders. The challenges and implementation of IE in selected Asian countries emerged as the meta-theme of the study. This study recommends that the respective governments and Teacher Education Institutions (TEIs) provide adequate fund allocation and revisit and strengthen existing laws and policies, professional development programs, and administrative support.

The continued scaling in transistors and memory elements has necessitated the development of atomic layer deposition (ALD) of silicon nitride (SiNx), particularly for use a low k dielectric spacer. One of the key material properties needed for SiNx films is a low wet etch rate (WER) in hydrofluoric (HF) acid. In this work, we report on the evaluation of multiple precursors for plasma enhanced atomic layer deposition (PEALD) of SiNx and evaluate the film’s WER in 100:1 dilutions of HF in H2O. The remote plasma capability available in PEALD, enabled controlling the density of the SiNx film. Namely, prolonged plasma exposure made films denser which corresponded to lower WER in a systematic fashion. We determined that there is a strong correlation between WER and the density of the film that extends across multiple precursors, PEALD reactors, and a variety of process conditions. Limiting all steps in the deposition to a maximum temperature of 350 °C, it was shown to be possible to achieve a WER in PEALD SiNx of 6.1 Å/min, which is similar to WER of SiNx from LPCVD reactions at 850 °C.

Le programme thermodynamique et cinétique KINDISP (KINetic of DISsolution and Precipitation) simule les interactions minéraux/solutions aqueuses en considérant la dissolution irréversible des réactants et la précipitation réversible ou irréversible des phases secondaires. Les lois générales introduites dans le modèle ont pour base théorique la Thermodynamique des Processus Irréversibles. Les interactions eaux/roches à basse température (25-30 °C) sont interprétées théoriquement à l'aide de la Théorie de l'Etat de Transition et de la Chimie de Coordination de Surface. Le mécanisme qui limite la vitesse de dissolution ou de précipitation d'un minéral, c'est-à-dire le mécanisme le plus lent pour les réactions irréversibles successives, est soit la diffusion moléculaire aqueuse d'une entité élémentaire (atome, molécule . . . ) ou bien la réaction de surface (adsorption-désorption d'une entité élémentaire). A chaque étape du calcul, caractérisé par un incrément de temps (dt), le modèle informatique KINDISP calcule les vitesses de réaction pour chaque minéral réactif dans le système eau-roche. A partir de ce calcul, le modèle compare les vitesses contrôlées par la diffusion moléculaire et par la réaction de surface. Ensuite, KINDISP retient la vitesse la plus lente pour représenter la loi de dissolution d'un minéral réactif primaire ou la loi de précipitation d'une phase néoformée secondaire. La croissance des minéraux secondaires est simulée, soit à l'équilibre thermodynamique, soit en domaine de sursaturation (en nonéquilibre), après une étape de nucléation, lorsque le point de sursaturation critique S* est atteint. Le programme géochimique KINDISP est divisé en deux ensembles : un module de calcul d'équilibre initial de la solution aqueuse appelé EQUILT et un module constitué de la procédure de perturbation par incréments de temps rendant compte de l'évolution géochimique du système eau-roche. Ainsi, après le calcul de la distribution ionique des éléments à partir de la composition chimique de la solution, c'est la dissolution irréversible d'un ou plusieurs minéraux réactifsqui va faire évoluer l'ensemble du système géochimique formé d'espèces aqueuses, de minéraux primaires et secondaires. Pour un incrément de temps dt, l'apport de matière en solution est fonction de la vitesse de dissolution des minéraux réactifs . L'intérêt du modèle thermodynamique et cinétique KINDISP par rapport à un modèle purement thermodynamique est le suivi de l'évolution géochimique du système eau-roche selon la durée des réactions, c'est-à-dire qu'il est réellement prédictif en fonction du temps. Le modèle KINDISP a été appliqué pour simuler des interactions eaux/roches naturelles ou induites. A basse température, on peut citer l'étude des effets de pluies acides sur l'altération superficielle d'un massif granitique, l'estimation du temps de formation d'un horizon latéritique et les effets de polluants sur l'environnement. A plus haute température (>60 °C), le programme KINDISP a permis de simuler la prise en compte de réactions diagénétiques dans les bassins sédimentaires en vue d'exploitation des réservoirs ou bien l'étude d'un système de réactions hydrothermales provoquées par un stockage de chaleur (géothermie . . . ) ou l'enfouissement de colis de déchets radioactifs. . . Le second article de la série présentera quelques résultats obtenus par le modèle géochimique KINDISP appliqué à l'étude du bassin pétrolier de la Mahakam en Indonésie (Brosse et al. , 1994). Most transformations on the earth's surface are controlled by the interactions between water and rocks. The minerals that make up the rocks react with aqueous solutions; primary minerals are dissolved, thus freeing ionic species in solution and secondary minerals precipitate at thermodynamic equilibrium or in an oversaturated domain. The alteration processes are usually very complex which is the reason why geochemical models have been developed to understand and simulate the reactions occurring between a set of minerals constituting a rock and an aqueous solution at thermodynamic disequilibrium. An important theoretical work (Helgeson, 1968), based on the pioneering achievements by Garrels and Thompson (1962), made it possible, during the 1970's, to develop numerical models. The primary aim of these computer codes was to calculate the speciation of aqueous solutions and their equilibrium in relation to a mineral paragenesis: SOLMNEQ (Kharaka and Barnes, 1973), WATEQ (Truesdell and Jones, 1974; Plummer et al, 1976), EQUIL (Fritz, 1975), MINEQL (Westall et al. , 1976), EQ3NR (Wolery and Walters, 1975; Wolery, 1979), are all examples of this first generation of models. Starting with these geochemical models, which were based on purely thermodynamic laws and therefore did not consider the rate of chemical reactions, others were developed that charted the way in which a water/rock system evolved through a succession of states of equilibrium. The driving force of the reaction is the progressive variation of one constraint in the system, either through irreversible dissolution of reactants, e. g. the models PATH1 (Helgeson et al. , 1969, 1970), DISSOL (Fritz, 1975, 1981), PHREEQE (Parkhurst et al. , 1980), EQ3/6 (Wolery, 1983; Devaler and Wolery, 1989), SOLMINEQ88 (Perkins et aL, 1990) or through temperature variation, e. g. THERMAL (Fritz, 1981), PHRQINPT (Flemming and Plummer, 1983) or yet, through evaporation of the aqueous solution as in EVAPOR (Fritz, 1981). Thus, the first models were based on thermodynamic equations where the evolution of the system was mapped as a function of the degree of progress of the reaction noted dzeta. More recently, new models have appeared that take into account kinetic laws, thus making it possible to estimate the time of the water/rock interactions and of their return to equilibrium, e. g. EQ6 (Helgeson and Murphy, 1983; Wolery et al. , 1990) and KINDIS (Madé and Fritz, 1992; Clément, 1992). In the course of the last few years, coupled chemistry-transport models have been built where chemical thermodynamic laws are introduced into the transport models. Lately, experimental studies of mineral dissolution kinetics have become more numerous, making available the data needed for the kinetic and thermodynamic modelling of water/rock interactions. At the moment, the constants of apparent dissolution rates of ubiquitous rock minerals and the various factors that influence the kinetics of reactions between minerals and aqueous solutions are accessible and recorded in several overview studies (Lasaga, 1984; Helgeson et al, 1984; Walther and Wood, 1986; Schott and Petit, 1987; Murphy and Helgeson, 1987,1989; Brady et Walther, 1989; Wieland et al. , 1988; Hochella and White, 1990; Stumm and Wollast, 1990; Stumm and Wieland, 1990; Madé,1991). Comparative studies have been made of the many existing geochemical and hydrogeological models used to represent water/rock interactions (Nordstrom et al, 1979; Meshri, 1990; Basset and Melchior, 1990; Mangold and Tsang, 1991; Plummer, 1992).

Dielectrics are an important class of materials that are ubiquitous in modern electronic applications. Even though their properties are important for the performance of devices, the number of compounds with known dielectric constant is on the order of a few hundred. Here, we use Density Functional Perturbation Theory as a way to screen for the dielectric constant and refractive index of materials in a fast and computationally efficient way. Our results constitute the largest dielectric tensors database to date, containing 1,056 compounds. Details regarding the computational methodology and technical validation are presented along with the format of our publicly available data. In addition, we integrate our dataset with the Materials Project allowing users easy access to material properties. Finally, we explain how our dataset and calculation methodology can be used in the search for novel dielectric compounds.

We demonstrate a high-throughput density functional perturbation theory (DFPT) methodology capable of screening compounds for their dielectric properties. The electronic and ionic dielectric tensors are calculated for 88 compounds, where the eigenvalues of the total dielectric tensors are compared with single crystal and polycrystalline experimental values reported in the literature. We find that GGA/PBE has a smaller mean average deviation from experiments (MARD=16.2%) when compared to LDA. The prediction accuracy of DFPT is lowest for compounds that exhibit complex structural relaxation effects (e.g., octahedra rotation in perovskites) and/or strong anharmonicity. Despite some discrepancies between DFPT results and reported experimental values, the high-throughput methodology is found to be useful in identifying interesting compounds by ranking. This is demonstrated by the high Spearman correlation factor (ρ=0.92). Finally, we demonstrate that DFPT provides a good estimate for the refractive index of a compound without calculating the frequency dependence of the dielectric matrix (MARD=5.7%).