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Layered materials play a crucial role in numerous essential structures, including adhesive connections, composite laminates, and various electronic components. This work focuses on proposing a novel framework of algorithms to improve the adaptability of element-free Galerkin method for modeling fracture in bimaterials exposed to thermoelastic loads. A bimaterial fracture problem is modeled as a combination of both weak and strong discontinuities — strong discontinuity owing to the presence of crack and weak discontinuity due to inherent material discontinuities. Initially, three distinct methods, comprising domain partitioning, lagrange multiplier, and jump function have been employed for interface crack modeling and error norm is used as an indicator to select the optimum one. Second, a novel interface enrichment algorithm has been introduced to effectively model the interface with limited computational costs with higher accuracy. Owing to the applicability of bimaterials in numerous applications under a combination of thermal/mechanical loads, the proposed formulation has been utilized for modeling and simulating a diverse bimaterial thermoelastic fracture problems using the proposed framework. The mixed mode (complex) stress intensity factors (SIFs) are numerically examined using modified domain form of interaction integral. A good agreement of results with available results from literature extends the computational prowess of the proposed framework in modeling a variety of thermoelastic bimaterial problems accurately and swiftly as compared to conventional EFGM.

An emerging concept, nanoarchitectonics, is supposed to work on the preparation of functional materials systems from nanoscale components. Because porphyrin derivatives show their importance in many research targets, discussions on nanoarchitectonics with porphyrins and related molecules would provide meaningful opportunities to consider effective usages of the nanoarchitectonics. This review article explains various examples of nanoarchitectonics approaches with porphyrin derivatives. The examples are especially focused on two topics: (i) materials nanoarchitectonics for nanofibers, metal-organic frameworks, covalent organic frameworks, and hydrogen-bonded organic frameworks; (ii) interfacial nanoarchitectonics for surface monolayers (self-assembled monolayers), Langmuir-Blodgett films, and layer-by-layer assemblies. Functions and properties can be enhanced upon their organization in specific dimensions and arrangements in nanostructured frameworks. In many cases, interface-specific organization would lead to advanced performances with high efficiency and specificity. Even though only limited examples are described here, various possibilities are actually suggested. Not limited to porphyrin families, nanoarchitectonics for functional materials has to be considered with a wide range of materials.

Nanoarchitectonics is the methodology for the architecture of nano-units of atoms, molecules, and nanomaterials to create functional material systems. This will integrate nanotechnology with other fields such as organic chemistry, supramolecular chemistry, material science, microfabrication technology, and bio-related sciences. Through this review, it is shown that nanoarchitectonics is important for the development of various functional materials. Porphyrins and their analogues are exemplified as important players in nanoarchitectonics strategies. The contents of this review can be briefly summarized as follows. First, recent examples of studies on porphyrins and their analogues, ranging from organic synthesis as basic research to biomedical applications as advanced usages, are presented. This demonstrates the broad utility of porphyrins as functional nano-units, from molecular nanoarchitectonics to material nanoarchitectonics. In subsequent sections, the organization and function of porphyrin assemblies by the Langmuir-Blodgett (LB) method and layer-by-layer (LbL) assembly are described as examples of nanoarchitectonics at interfaces. The creation of functional materials through nanoarchitectonics is rich in possibilities. Conversely, the wide range of possibilities may make it difficult to easily design and control. Confine the system from free three-dimensional space to a two-dimensional field such as an interface, and design, creation, and evaluation may become easier. The nanoarchitectonics of functional structures in a two-dimensional plane are also advantageous in terms of functional expression. The use of interfacial environments is an extremely powerful tool for creating functional systems through nanoarchitectonics.

The interface behavior may significantly influence the mechanical properties of carbon nanotube (CNT)-reinforced composites due to the large interface area per unit volume at the composite. The modeling of CNT/polymer interfaces has been a challenge in the continuum modeling of CNT-reinforced composites. This paper presents a review of recent progress to model the CNT/matrix interfaces via a cohesive law established from the van der Waals force. A simple, analytical cohesive law is obtained from the inter-atomic potential, and is used to study the effect of CNT/matrix interfaces on the macroscopic properties of CNT-reinforced composites.

To reveal the wear mechanism of hyperbranched polysilane (HBPSi) grafted multi-walled carbon nanotubes (HBPSi–MWCNTs) modified benzoxazine–bismaleimide (BOZ–BMI) resin (HBPSi–MWCNTs/BOZ–BMI), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) were employed. The results indicated that the suitable addition of HBPSi–MWCNTs could largely enhance the tribological properties of BOZ–BMI composites. The worn surface of the composites showed that the severe wear of the BOZ–BMI resin was converted from adhesive wear to abrasive wear with the addition of HBPSi–MWCNTs. The excellent tribological properties can be attributed to the improved interfacial adhesion between HBPSi–MWCNTs and the BOZ–BMI resin matrix. The TGA demonstrated that the composite with 0.8wt.% HBPSi–MWCNTs exhibits better thermal resistance; thus, it can inhibit adhesive wear during the friction process. The XPS spectra and the surface energy showed that the HBPSi–MWCNTs could be exposed on the worn surface of the composite to improve the anti-wear capacity of the composites further.

Defects and stress distribution in the interface of Ge/Si hetero-structures play an important role in silicon-based semiconductor devices. This work at atomic scale performs molecular dynamics simulations to study the packing characteristics in the Ge/Si interface and loading features on the atoms for different contacting configurations between Ge nanopillars and Si substrates. Based on the analysis of energy, composition, the distribution of hydrostatic pressure, the Lode–Nadai parameters of each atom as well as visualized atomic packing images in the interface regions, simulation results show that contacting configurations of the Ge nanopillar with the (100) surface and the (110) surface of the Si substrate significantly affect the stability of the interface structures. The load-bearing positions of the Si surface and the inter-diffusion among the atoms in the interface regions greatly contribute to the lattice distortion of the silicon substrate, the composition, defects, and local stress distribution in the interface regions.

Metal-oxide nanoparticles with high surface area, controllable functionality and thermal and mechanical stability provide high affinity for enzymes when the next generation of biosensor applications are being considered. We report on the synthesis of metal-oxide-based nanoparticles (with different physical and chemical properties) using hydrothermal processing, photo-deposition and silane functionalization. Physical and chemical properties of the user-synthesized nanoparticles were investigated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Raman scattering, respectively. Thus, characterized metal-oxide-based nanoparticles served as nanosupports for the immobilization of soybean peroxidase enzyme (a model enzyme) through physical binding. The enzyme–nanosupport interface was evaluated to assess the optimum nanosupport characteristics that preserve enzyme functionality and its catalytic behavior. Our results showed that both the nanosupport geometry and its charge influence the functionality and catalytic behavior of the bio-metal-oxide hybrid system.

Retention of veneering materials to the tooth influences the survival rate in which depends primarily on an adequate adhesive bonded to enamel and ceramic substrates. Microleakages associated with resin monomers penetrating in enamel–etched porosities arise as the key issue to cause crack propagation and induce de-bonding in adhesive layer. The aim of this study is to investigate the micromechanical responses and crack propagation in a ceramic veneer adjacent to an incisal-overlapped incisor using the finite element (FE) submodeling and the element deactivation techniques. Section contours of an intact maxillary central incisor were acquired from microcomputed tomography (CT) to construct a three-dimensional (3D) FE macromodel considered with butt joint veneer design using mapping mesh approach. Ten loads from 10 to 100 N increments with 10 N were applied with an angulation of 60° to the tooth longitudinal axis at the incisal edge in the macromodel as the loading conditions to perform the simulations. The micromodel was constructed at an enamel–adhesive interface, where was the stress concentration area in the macromodel. The morphology and dimensions of the resin tags at the interface were assigned based on a SEM micrograph. Boundary conditions of the micromodel were determined from the macromodel results. An iterative code with the element deactivation technique was used while the local element stresses exceeding a self-testing tensile strength in adhesive layer to simulate the microcrack propagation. Stress concentration within the adhesive occurred at the enamel–adhesive interface of the lingual edge from the macromodels findings and at their resin tags base from the micromodels results. The maximum stress value in the micromodel exceeded the tensile strength (11.8 MPa) of resin cement when loading condition was 50 N. A simulated fracture path was found at the resin tags base along the enamel–adhesive interface from lingual to labial side. This study indicated that the FE submodeling and the element deactivation techniques could simulate efficiently the micromechanical responses and the microcrack propagation noted at the enamel–adhesive interface in the veneer system.

The increasing amount of available Protein-Protein Interaction (PPI) data enables scalable methods for the protein complex prediction. A protein complex is a group of two or more proteins formed by interactions that are stable over time, and it generally corresponds to a dense sub-graph in PPI Network (PPIN). However, dense sub-graphs correspond not only to stable protein complexes but also to sets of proteins including dynamic interactions. As a result, conventional simple PPIN based graph-theoretic clustering methods have high false positive rates in protein complex prediction. In this paper, we propose an approach to predict protein complexes based on the integration of PPI data and mutually exclusive interaction information drawn from structural interface data of protein domains. The extraction of Simultaneous Protein Interaction Cluster (SPIC) is the essence of our approach, which excludes interaction conflicts in network clusters by achieving mutually exclusion among interactions. The concept of SPIC was applied to conventional graph-theoretic clustering algorithms, MCODE and LCMA, to evaluate the density of clusters for protein complex prediction. The comparison with original graph-theoretic clustering algorithms verified the effectiveness of our approach; SPIC based methods refined false positives of original methods to be true positive complexes, without any loss of true positive predictions yielded by original methods.