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Phyllostachys angusta McClure is a precious wood-use bamboo resource, with almost straight stem. The complete chloroplast genome of the P. angusta McClure was assembled for the first time from Illumina pair-end sequencing data in this work. The total genome size of P. angusta McClure was 139,678 bp in length, containing a large single-copy (LSC) region of 83,212 bp, a small single-copy (SSC) region of 12,870 bp, and a pair of inverted repeat (IR) regions of 21,798 bp. The overall GC content of the genome was 38.89%, and the corresponding values of the LSC, SSC, and IR regions were 36.97, 33.17, and 44.22%, respectively. A total of 131 genes were annotated, including 85 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. Phylogenetic analysis results strongly supported that P. angusta McClure was closely related to P. reticulate.

Gel spinning of UHMWPE fibers using low molecular weight polybutene (PB) as a new spin solvent was investigated. A 98/2 wt% PB/UHMWPE gel exhibits a melting temperature around 115°C and shows large-scale phase separation upon cooling the solution to room temperature. The resulting precursor fiber from this gel was hot-drawn to a ratio of 120, yielding a fiber with tensile strength of 4 GPa and Young's modulus of over 150 GPa. Wide-angle X-ray diffraction indicates good molecular orientation along the fiber axis. The results also demonstrate the potential to further improve the mechanical properties. With respect to the gel spinning industry, this new solvent has a number of advantages over paraffin oil and decahydronaphthalene, and holds a promise of greatly improving the process efficiency., INTRODUCTION High performance polyethylene (PE) fibers continue to replace conventional materials in many military and civilian applications such as composites, ropes, and textiles. The success of these fibers owes largely [...]

In this work, a microwave expansion process to produce thermoset-matrix syntactic foam containing thermoplastic foam beads was designed and developed. Expandable polystyrene (EPS) microspheres and epoxy resin were chosen as a model material system. This process is featured with a capability to effectively expand EPS microspheres in syntactic foam with high EPS loading. The resin viscosity and specific microwave energy are found to be the two primary control parameters determining the process window. Mechanical characterization showed that the specific flexural strength and modulus of the syntactic foam are similar to those of the neat epoxy. By comparison, the flexural moduli over density squared or cubed of the foam are much higher, especially at high EPS loadings, than those of the neat resin. The foamed EPS microspheres can also effectively toughen the syntactic foam, preventing propagation of cracks. Furthermore, the microwave expansion process was found to be capable of molding syntactic foam parts of relatively sophisticated geometry with smooth surfaces., INTRODUCTION Syntactic foam is a special kind of gas-filled polymeric materials in which microballoons or foamed microspheres are embedded uniformly in a polymer matrix designated as a binder [1]. Different [...]

Composite polystyrene foam with a honeycomb-like barrier structure was processed from an expandable aqueous suspension. Optical observations confirmed the formation of such a unique structure that encapsulates each expanded polystyrene microsphere in the resulting foam. The suspension viscosity was found to highly influence the foam morphology. Results from mechanical tests showed that the existence of the barrier structure can considerably improve the mechanical performance of the composite foam. Fire retardation tests demonstrated that the barrier structure can effectively stop the fire path into the foam, suppress toxic smoke generation, and maintain structural integrity, leading to improved fire resistance in comparison with the neat polystyrene foam., INTRODUCTION Expandable polystyrene (EPS) is the raw material used for molding foamed polystyrene products. It is manufactured into small-diameter polystyrene microspheres containing physical blowing agents, usually pentane or butane. When [...]

The Li dendrite growth and the liquid electrolyte volatilization under semi-open architecture are intrinsic issues for Li-O2 battery. In this work, we propose a non-Newtonian fluid quasi-solid electrolyte (NNFQSE) SiO2-SO3Li/PVDF-HFP, which has both shear-thinning and shear-thickening properties. The component interactions among the sulfonated silica nanoparticles, liquid electrolyte, and polymer network are beneficial for decent Li+ conductivity and high liquid electrolyte retention without volatilization. Furthermore, NNFQSE exhibits shear-thinning property to eliminate the stress of dendrite growth during repeated cycling. Meanwhile, when the force suddenly increases, such as a high current rate, the NNFQSE may dynamically turn shear-thickening to respond and mechanically stiffen to inhibit the lithium dendrite penetration. By coupling with the NNFQSE, the lithium symmetrical battery can run over 2000 h under 1 mA cm−2 at room temperature, and the quasi-solid Li-O2 battery actualizes long life above 5000 h at 100 mA g−1. Lithium dendrite growth and liquid electrolyte volatilization limit the further development of lithium-oxygen batteries. Here, authors report a non-Newtonian fluid quasi-solid electrolyte to address those issues, which improve the life duration of the lithium-oxygen batteries. [ABSTRACT FROM AUTHOR]

A microsphere templating process was recently developed for fabrication of open-cell porous elastomer. The material contained a unique cocontinuous structure having micropores interconnected by microchannels. In this work, a follow-up study was conducted to investigate the mechanical behavior of such porous materials. Polysiloxane was chosen as a model material. The deformation characteristics and mechanical properties of the porous elastomer under tension and compression were then studied. For both tensile and compressive tests, the mechanical properties measured were found to largely deviate from those calculated by the additive rule assuming affine deformation. This nonaffine mechanics was further verified by microscopic observations. Cyclic loading and unloading tests were also performed to study the hysteresis of the material. In comparison with the solid elastomer, the hysteresis of the porous elastomer was considerably higher and more sensitive to the strain rate. An attempt was further made to fit the stress-strain curve using existing hyperelastic models, and the results showed that the Arruda-Boyce model, in general, fit both the solid and porous polysiloxane very well., INTRODUCTION There has been a growing interest in developing interconnected porous elastomers, primarily driven by many emerging applications in the biomedical field [1-7]. Currently, salt leaching is the most widely [...]