338 research outputs found
Geometric characteristics of 3D reconstructed anode electrodes of lithium ion batteries
The realistic 3D microstructure of lithium ion battery electrodes
plays a key role in studying the effects of inhomogeneous microstructures on
the performance of LIBs. However, the complexity of realistic
microstructures implements significant computational cost on numerical
simulation of large size samples. In this work, we used tomographic data
obtained for a commercial lithium ion battery graphite electrode to evaluate
the geometric characteristics of the reconstructed electrode microstructure.
Based on the analysis of geometric properties, such as porosity, specific
surface area, tortuosity, and pore size distribution, a representative volume
element that retains the geometric characteristics of the electrode material
was obtained for further numerical studies. In this work, X-ray micro-CT with
0.56 μm resolution was employed to capture the inhomogeneous porous
microstructures of lithium ion battery anode electrodes. The Sigmoid
transform function was employed to convert the initial raw tomographic
images to binary images. Moreover, geometric characteristics of an anode
electrode after 2400 1 C charge/discharge cycles were compared with those of
a new anode electrode to investigate morphological change of the electrode.
In general, the cycled electrode shows larger porosity, smaller tortuosity, and
similar specific surface area compared to the new electrode
Iron Deficiency Anaemia
Iron deficiency anaemia as the most common nutrition disorder has only marginal reduction globally during recent decades, with the highest burden in pregnant women and young children. Insufficient iron storage and/or excessive loss of iron are common causes of iron deficiency anaemia. Therefore, understanding the complexity of the regulatory network required to maintain iron homeostasis and identifying the functional variants associated with iron metabolism should be fundamental and crucial to control and treat the iron deficiency anaemia. Sensitive and inexpensive measures to distinguish iron deficiency anaemia from the other kinds of anaemia should be developed for precise treatment. Original disease treatments combined with oral or intravenous iron therapy are key approaches in clinical practices. The integrated, multifactorial and multi‐sectoral approach with food‐based strategy and iron supplementation as the leading public health inventions is required to achieve iron deficiency anaemia control target. This chapter will focus on the advanced knowledge associated with iron metabolism, disease burden and health consequences of iron deficiency anaemia in different life course, newly parameters development in the diagnosis of iron deficiency anaemia, therapy choice in clinical practice and public health strategies to reduce iron deficiencies in high‐burden areas
3D Simulation of diffusion induced stress in realistic LiCoO2 electrode particles of lithium ion battery generated by nano-CT
Diffusion induces stresses in the electrode during charge and discharge processes of lithium ion batteries, which can cause deformation and even fracture, further result in the fade of capacity and duration. The 3D model coupling diffusion and induced stress is applied to the reconstructed LiCoO2 electrode particles determined by X-ray nanocomputed tomography technology, of which the nonuniform electrochemical intercalation reaction takes place on the surface. A code is developed to simulate the fully coupled diffusion and induced stress in the LiCoO2 electrode particles at different discharge rates. The simulations demonstrate the variable distribution such as concentration, reaction rate, hydrostatic stress, Von-Mises stress, and so on. The influence of the geometric characteristics of LiCoO2 electrode particle and material properties on the variables is revealed. The investigation can help to improve lithium ion battery design and manufacture through understanding the relationship between electrode morphology and mechanical endurance
Wanting Ever More: Accumulation Procedure Motivates Continued Possession Acquisition
Three experiments show that a piecemeal procedure for acquiring material possessions, whereby a quantity of possessions is acquired gradually through repeated small efforts, is more motivating than a lump-sum procedure to acquire the same amount of possessions. This is because a piecemeal procedure results in a greater sense of achievement
Surgery for Complete Vertical Rectus Paralysis Combined with Horizontal Strabismus
Aims. To report outcomes of the simultaneous surgical correction of vertical rectus paralysis combined with moderate-to-large angle horizontal strabismus. Methods. If a preoperative forced duction test was positive, antagonist muscle weakening surgery was performed, and then augmented partial rectus muscle transposition (APRMT) + partial horizontal rectus recession-resection was performed 2 months later. If a preoperative forced duction test was negative, APRMT + partial horizontal rectus recession-resection was performed. Antagonistic muscle weakening surgery and/or conventional recession-resection of the horizontal and/or vertical muscles of the contralateral eye was performed 2 months later, as needed. Results. Ten patients with a mean age of 22.3 ± 13.0 years were included and mean follow-up was 7.1 months. The mean vertical deviation that APRMT corrected was 21.4 ± 3.7 PD (prism diopter). The absolute deviation in horizontal significantly decreased from a preoperative value of 48.5 ± 27.4 PD to a value of 3.0 ± 2.3 PD 6 months postoperatively. The movement score decreased from a value of −5 ± 0 preoperatively to a value of −2.7 ± 0.8 at 6 months postoperatively. Conclusion. For patients with complete vertical rectus paralysis combined with a moderate- to-large angle of horizontal strabismus, combined APRMT and partial horizontal rectus recession-resection is safe and effective for correcting vertical and horizontal strabismus
RGD Peptide-Grafted Graphene Oxide as a New Biomimetic Nanointerface for Impedance-Monitoring Cell Behaviors
A new biomimetic nanointerface was constructed by facile grafting the bioactive arginylglycylaspartic acid (RGD) peptide on the graphene oxide (GO) surface through carbodiimide and N-hydroxysuccinimide coupling amidation reaction. The formed RGD-GO nanocomposites own unique two-dimensional structure and desirable electrochemical performance. The linked RGD peptides could improve GO’s biocompatibility and support the adhesion and proliferation of human periodontal ligament fibroblasts (HPLFs) on RGD-GO biofilm surface. Furthermore the biologically active RGD-GO nanocomposites were demonstrated as a potential biomimetic nanointerface for monitoring cell biobehaviors by electrochemical impedance spectroscopy (EIS). By analysis of the data obtained from equivalent circuit-fitting impedance spectroscopy, the information related to cell membrane capacitance, cell-cell gap resistance, and cell-electrode interface gap resistance in the process of cell adhesion and proliferation could be obtained. Besides, this proposed impedance-based cell sensor could be used to assess the inhibition effect of the lipopolysaccharide (LPS) on the HPLFs proliferation. Findings from this work suggested that RGD peptide functionalized GO nanomaterials may be not only applied in dental tissue engineering but also used as a sensor interface for electrochemical detection and analysis of cell behaviors in vitro
LES/FGM investigation of ignition and flame structure in a gasoline partially premixed combustion engine
This paper presents a joint numerical and experimental study of the ignition process and flame structures in a gasoline partially premixed combustion (PPC) engine. The numerical simulation is based on a five-dimension Flamelet-Generated Manifold (5D-FGM) tabulation approach and large eddy simulation (LES). The spray and combustion process in an optical PPC engine fueled with a primary reference fuel (70% iso-octane, 30% n-heptane by volume) are investigated using the combustion model along with laser diagnostic experiments. Different combustion modes, as well as the dominant chemical species and elementary reactions involved in the PPC engines, are identified and visualized using Chemical Explosive Mode Analysis (CEMA). The results from the LES-FGM model agree well with the experiments regarding the onset of ignition, peak heat release rate and in-cylinder pressure. The LES-FGM model performs even better than a finite-rate chemistry model that integrates the full-set of chemical kinetic mechanism in the simulation, given that the FGM model is computationally more efficient. The results show that the ignition mode plays a dominant role in the entire combustion process. The diffusion flame mode is identified in a thin layer between the ultra fuel-lean unburned mixture and the hot burned gas region that contains combustion intermediates such as CO. The diffusion flame mode contributes to a maximum of 27% of the total heat release in the later stage of combustion, and it becomes vital for the oxidation of relatively fuel-lean mixtures
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