This study focuses on the role played by the interparticle and interlayer porosities, and the preferred orientation of the particles on water diffusion in dual-porosity clayey media (i.e., swelling clay minerals). For this purpose, we use Na-vermiculite, a swelling clay that does not exhibit osmotic swelling and therefore allows a clear discrimination between the interparticle and interlayer porosities. Two samples were prepared with an equal proportion of interparticle and interlayer porosities (i.e., 0.25 each) but different degree of preferred particle orientation (i.e., isotropic vs anisotropic). Through-diffusion and pulsed gradient spin echo attenuation measurements by nuclear magnetic resonance of protons techniques were used to probe water mobility, while the orientation of the particles was quantified by X-ray scattering analysis.Experimental water diffusion results obtained with these two Na-vermiculite samples were compared to those with samples made of Na-kaolinite particles (non-swelling clay mineral) having only interparticle porosities equal to 0.25 and 0.5, corresponding respectively to the interparticle and the total porosity of the Na-vermiculite samples. In addition, these experimental results were compared to simulated data using Brownian dynamics with virtual porous media representative of the real samples. For the range of porosities investigated, a good agreement was observed between measured and simulated water mobilities. The obtained results confirmed the important role played by the preferential orientation of the particles on water dynamics in clayey media, through an important reduction of overall water mobility between the isotropic and anisotropic Na-vermiculite samples. These results also showed that for the same total porosity, the presence of interlayer porosity and associated nano-confinement led to a logical reduction in the pore diffusion coefficient of water in Na-vermiculite in comparison to Na-kaolinite. Moreover, in comparison with Na-kaolinite having the same interparticle porosity, results showed that the contribution of the interlayer volume on the traversing flux was small compared to the interparticle volume. Finally, the computed results revealed that the anisotropy in water diffusion can be directly predicted based on the degree of particles preferred orientation, irrespective of the total or the distribution of the different porosity types.

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Distribution system planners and operators have increasingly exposed great attention to maximizing the penetration of renewable energy resources (RERs), and electric vehicles (EVs) toward modern microgrids. Accordingly, intensive operational and economic problems are expected in such microgrids. Specifically, the operators need to meet the increased demand for EVs and increase the dependence on RERs. The charging strategy for EVs and the RER penetration level may result in increased power loss, thermal loading, voltage deviation, and overall system cost. To address these concerns, this paper proposed an optimal planning approach for allocating EV charging stations with controllable charging and hybrid RERs within multi-microgrids, where the charging strategy in the proposed planning approach contributed to improving power quality and overall system cost, where the voltage deviation, energy not supplied, total cost have been reduced to 26.03%, 49.57%, and 70.45%, respectively. The simulation results are compared with different optimization techniques to verify the effectiveness of the proposed algorithm. The proposed simultaneous allocation approach of EV charging stations and RERs can reduce operating costs for RERs and conventional stations while increasing the charging stations' capacity.

This review details a large panel of experimental studies (Inelastic Neutron Scattering, Quasi-Elastic Neutron Scattering, Nuclear Magnetic Resonance relaxometry, Pulsed-Gradient Spin-Echo attenuation, Nuclear Magnetic Resonance Imaging, macroscopic diffusion experiments) used recently to probe, over a large distribution of characteristic times (from pico-second up to days), the dynamical properties of water molecules and neutralizing cations diffusing within clay/water interfacial media. The purpose of this review is not to describe these various experimental methods in detail but, rather, to investigate the specific dynamical information obtained by each of them concerning these clay/water interfacial media. In addition, this review also illustrates the various numerical methods (quantum Density Functional Theory, classical Molecular Dynamics, Brownian Dynamics, macroscopic differential equations) used to interpret these various experimental data by analyzing the corresponding multi-scale dynamical processes. The purpose of this multi-scale study is to perform a bottom-up analysis of the dynamical properties of confined ions and water molecules, by using complementary experimental and numerical studies covering a broad range of diffusion times (between pico-seconds up to days) and corresponding diffusion lengths (between Angstroms and centimeters). In the context of such a bottom-up approach, the numerical modeling of the dynamical properties of the diffusing probes is based on experimental or numerical investigations performed on a smaller scale, thus avoiding the use of empirical or fitted parameters.

Background This case report describes a cystic fibrosis case after 7 years of a presumed diagnosis of celiac disease without confirming laboratory tests and biopsies. Both cystic fibrosis and celiac disease cause malnutrition, malabsorption, and failure to thrive. Also, the occurrence of cystic fibrosis in celiac disease patients is higher than in the normal population. Therefore, the differentiation between the two diseases might be challenging. This article highlights the reason for the confusion between cystic fibrosis and celiac disease and emphasizes the importance of not skipping the necessary investigations no matter how difficult it is to perform them. Case presentation This report details the case history of a patient presumed to have celiac disease for 7 years without confirming investigations. He developed multiple respiratory infections and weight loss throughout the 7 years but was only diagnosed with cystic fibrosis after hospitalization for gradual abdominal distension and productive cough. Chest CT showed atelectasis in the right upper lobe, tree-in-bud sign on both sides, and right periumbilical mass with several enlargements in the mediastinal nodes. Ascites paracentesis revealed a high SAAG gradient and low-protein fluid. The sweat chloride test resulted in a chloride level of 90 mEq/L, which confirmed the cystic fibrosis diagnosis. Subsequent genetic testing revealed the rare G85E mutation. Conclusion This report highlights the potential for diagnostic confusion between cystic fibrosis and celiac disease. Also, it reminds physicians about the importance of taking a detailed medical history and performing the essential investigations no matter how difficult it is to do them. Finally, it emphasizes the need to verify the patient’s previous medical history in case there is no official documentation of his case. This should be considered particularly in rural areas in low-income countries where the possibility of medical malpractice should not be forgotten.

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