Search

In this paper, we study the nonlinear dynamics of a multiplex system consisting of neuronal networks each with an arbitrary number of FitzHugh-Nagumo neurons and intra-connections and delayed couplings. The network contains an autaptic connection formed by the axon of a neuron on its own soma or dendrites. The stability and instability of the network are determined and the existence of bifurcation is discussed. Then, the study turns to validate the theoretical analysis through numerical simulations. Abundant dynamical phenomena of the network are explored, such as coexisting multi-period oscillations and chaotic responses. [ABSTRACT FROM AUTHOR]

To study the effect of the precuring rate of impregnated fluffed veneers (IFVs) on the bonding performance of scrimber, the precuring rate of IFVs following different drying conditions was characterized by fluorescence microscopy. The phenol formaldehyde (PF) solid content, drying temperature, and time were assessed using orthogonal tests. The moisture content, precuring rate of the dried IFVs, and bonding strength of the scrimber were evaluated. The results showed that the moisture content of the IFVs was mainly affected by the PF solid content, while the precuring rate of the impregnated IFVs was primarily impacted by the drying temperature. A solid PF content of 20% and optimum drying conditions of 60 °C and 1.5 h were associated with a precuring rate of 12.3% of the PF resin on the surface of the IFVs, obtaining scrimber with the best bonding performance of 2.95 MPa. [ABSTRACT FROM AUTHOR]

Environmentally friendly fabrication of engineered bamboo lumber is enabled by the application of renewable, formaldehyde-free bio-adhesives. In this study, protein-based adhesives made from pig blood (PB) were developed for this purpose. PB was modified by alkali (NaOH) and glutaraldehyde into either alkali-modified pig blood adhesive (APB), glutaraldehyde-modified pig blood adhesive (GPB), or alkali-and-glutaraldehyde-modified pig blood adhesive (AGPB), which were expected to be more water-resistant. Two-ply laminated bamboo lumber samples were assembled, and their bonding strengths were measured. The thermal properties, presence of functional groups, and cross-sectional micro-morphologies of the modified adhesives and unmodified PB were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The thermal stabilities of all the modified adhesives were improved compared to that of the unmodified PB. FTIR confirmed that the NaOH treatment successfully induced the unfolding of the PB protein, exposing the hydrophobic groups in the APB and that glutaraldehyde became grafted onto primary amides in the AGPB. Compared with the PB and APB, the cross-sectional micro-morphologies of the GPB and AGPB were more homogeneous and compact. The wet shear strength of the laminated bamboo lumber (LBL) was clearly increased by the modified adhesives. The AGPB had a higher wet shear strength of 4.6 MPa. Thus, the GPB and AGPB can be considered as potential protein adhesives for use in a variety of engineered bamboo products. [ABSTRACT FROM AUTHOR]