Isogeometric analysis on sandwich plates5 answersIsogeometric analysis (IGA) has been used in several papers to analyze the static, dynamic, and buckling behavior of laminated and functionally graded (FG) sandwich plates. The use of IGA allows for the implementation of nonpolynomial shear deformation theories (NPSDT) and third-order shear deformation theories (TSDT) in the analysis, which consider the nonlinear distribution of transverse shear stresses and satisfy the transverse shear deformation conditions at the top and bottom surfaces of the plates. The multi-patch B-spline basis functions used in IGA ensure C0-continuity at layer interfaces and smoothly varying material properties across each layer thickness. Additionally, a quasi three-dimensional (quasi-3D) shear deformation theory has been proposed, which uses isogeometric analysis and physical neutral surface position to satisfy the free transverse shear stress conditions without the need for shear correction factors. The use of inverse tangent shear deformation theory (ITSDT) in combination with IGA has also been explored for laminated composite and sandwich plates, eliminating the need for shear correction factors and achieving high efficiency. Finally, a fifth-order shear deformation theory (FiSDT) combined with IGA has been used for the analysis of composite sandwich plates, providing accurate results for static, dynamic, and buckling analysis.
Isogeometric analysis on sandwich structures5 answersIsogeometric analysis has been used in several studies to analyze sandwich structures. One study introduced an equilibrium-based stress recovery approach for determining the three-dimensional stress state in composite sandwich plates using isogeometric analysis. Another study performed buckling and vibration studies of sandwich plates with a negative Poisson's ratio honeycomb core using isogeometric analysis. A highly accurate and computationally efficient isogeometric beam element was presented for displacement and stress analysis of thin/thick composite beams. Additionally, effective numerical approaches based on isogeometric analysis were proposed for the static and dynamic analysis of laminated and sandwich composite plates. These studies demonstrate the applicability and advantages of isogeometric analysis in analyzing the behavior of sandwich structures.
How to improve graphene aerogel retention?4 answersTo improve the retention of graphene aerogel, several methods have been proposed in the literature. One approach is to attach chemically modified graphene sheets to the aerogel pore surface, which enhances hydrophobicity without compromising porosity and elasticity. Another method involves the use of dendrimer-modified graphene oxide aerogels, where the addition of carbon nanotubes improves functionalization and reduction, leading to enhanced CO2 adsorption performance. The hydrothermal reaction time during the synthesis of graphene aerogel also plays a crucial role in its adsorption abilities. Increasing the reaction time enhances the interaction between the aerogel and adsorbates, resulting in higher adsorption capacities. Additionally, a natural drying preparation method using borate crosslinking effect has been proposed, which enhances the rigidity of the aerogel and reduces capillary forces during drying. Finally, a method involving the immobilization of transition metal nano particles in a polymer gel followed by calcination has been shown to increase the active sites and improve the activity of graphene metal-based aerogels.
Isometricts in strength training4 answersIsometric strength training has been shown to have positive effects on various aspects of athletic performance. Studies have found that isometric training with weights can significantly improve explosive strength in soccer players' lower limbs. Isometric and isotonic training protocols have been found to improve health-related fitness components in young adults, with isotonic training being more efficient in increasing muscle strength, muscular endurance, and flexibility. Long-term inclusion of isometric strength training has been shown to result in greater improvements in sprint performance compared to control groups. Isometric training can be beneficial for athletes in various ways, such as avoiding excessive fatigue, improving strength at specific joint positions, and enhancing sports-specific movements that require isometric contractions. Isometric resistance training has also been found to increase muscle activity and improve the energy conversion capacity in the muscle-tendon complex.
What is the difference between isostatic equilibrium and isostatic disequilibrium?5 answersIsostatic equilibrium refers to a state in which the Earth's crust is in balance, with the forces of gravity and buoyancy evenly distributed. It occurs when the lithosphere is supported by the asthenosphere, and there is no vertical movement or deformation. Isostatic disequilibrium, on the other hand, occurs when there is an imbalance in the forces acting on the crust, leading to vertical movement and deformation. This can be caused by various factors such as tectonic activity, erosion, or the addition or removal of material from the crust. The abstracts provide insights into different aspects of equilibrium and disequilibrium. Zhang et al.discuss the trace element responses to equilibrium and disequilibrium melting processes in granite petrogenesis. Labouvie-Viefexplores the role of equilibrium and disequilibrium in learning about emotion regulation. Frederiksen et al.investigate the crustal thickness and composition changes associated with isostatic disequilibrium along the North Anatolian Fault Zone. Scodina et al.analyze the formation of coronitic textures in rocks and the role of slow reaction kinetics in preserving igneous phases during corona formation.
What are the different methods for characterizing graphite?5 answersDifferent methods for characterizing graphite include instrumental neutron activation analysis (INAA) combined with prompt gamma activation analysis (PGAA) and inductively coupled plasma mass spectrometry (ICP-MS). Another method involves using molecular dynamics (MD) simulation to investigate the mechanical properties of graphite, such as Young's modulus, Poisson's ratio, and shear modulus. Additionally, the growth stages of graphite in ductile irons can be analyzed using techniques such as Focused Ion Beam (FIB), Energy Dispersive X-ray (EDX), Transmission Kikuchi Diffraction (TKD), and Transmission Electron Microscopy (TEM). Furthermore, a method combining O2 supply and micro surface area of graphite has been proposed to characterize the thermal-oxidation behaviors of nuclear graphite. These methods provide valuable insights into the impurity distribution, material properties, and oxidation rate of graphite.