In this paper we develop a numerical method for two-dimensionaltime-dependent reaction-diffusion problems. This method, whichcan immediately be generalized to higher dimensions, is shownto be uniformly convergent with respect to the diffusion problems.This method, which can immediately be generalized to higherdimensions, is shown to be uniformly convergent with respectto the diffusion parameter. 相似文献
Layer‐by‐layer (LbL) assembly has emerged as the leading non‐vacuum technology for the fabrication of transparent, super gas barrier films. The super gas barrier performance of LbL deposited films has been demonstrated in numerous studies, with a variety of polyelectrolytes, to rival that of metal and metal oxide‐based barrier films. This Feature Article is a mini‐review of LbL‐based multilayer thin films with a ‘nanobrick wall’ microstructure comprising polymeric mortar and nanoplatelet bricks that impart high gas barrier to otherwise permeable polymer substrates. These transparent, water‐based thin films exhibit oxygen transmission rates below 5 × 10‐3 cm3 m‐2 day‐1 atm‐1 and lower permeability than any other barrier material reported. In an effort to put this technology in the proper context, incumbent technologies such as metallized plastics, metal oxides, and flake‐filled polymers are briefly reviewed.
Stromal cell-derived factor 1 (SDF-1 or CXCL12) is chemotaxic for CXCR4 expressing bone marrow-derived cells. It functions
in brain embryonic development and in response to ischemic injury in helping guide neuroblast migration and vasculogenesis.
In experimental adult stroke models SDF-1 is expressed perivascularly in the injured region up to 30 days after the injury,
suggesting it could be a therapeutic target for tissue repair strategies. We hypothesized that SDF-1 would be expressed in
similar temporal and spatial patterns following hypoxic-ischemic (HI) injury in neonatal brain. 相似文献
Cellulose - Relatively simple flame retardant finishing technologies for cotton are greatly desired in a variety of fire-sensitive applications (e.g., transportation, workwear, etc.). Many current... 相似文献
Carbon nanotubes typically require the use of a dispersing or stabilizing agent to prevent significant aggregation during incorporation into a polymer matrix. These additives must be strongly associated, either covalently or physically, to achieve their purpose. In this study, multi‐walled carbon nanotubes (MWNTs) were dispersed into an epoxy matrix using polyethylenimine (PEI) as a dispersant that was either covalently attached to the nanotubes or physically mixed to result in only noncovalent interaction. Epoxy composites containing covalently modified MWNTs exhibited greater storage modulus and reduced electrical conductivity.