19 research outputs found
Architectural Growth of Cu Nanoparticles Through Electrodeposition
Cu particles with different architectures such as pyramid, cube, and multipod have been successfully fabricated on the surface of Au films, which is the polycrystalline Au substrate with (111) domains, using the electrodeposition technique in the presence of the surface-capping reagents of dodecylbenzene sulfonic acid and poly(vinylpyrrolidone). Further, the growth evolution of pyramidal Cu nanoparticles was observed for the first time. We believe that our method might open new possibilities for fabricating nanomaterials of non-noble transition metals with various novel architectures, which can then potentially be utilized in applications such as biosensors, catalysis, photovoltaic cells, and electronic nanodevices
Anisotropic nanomaterials: structure, growth, assembly, and functions
Comprehensive knowledge over the shape of nanomaterials is a critical factor in designing devices with desired functions. Due to this reason, systematic efforts have been made to synthesize materials of diverse shape in the nanoscale regime. Anisotropic nanomaterials are a class of materials in which their properties are direction-dependent and more than one structural parameter is needed to describe them. Their unique and fine-tuned physical and chemical properties make them ideal candidates for devising new applications. In addition, the assembly of ordered one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) arrays of anisotropic nanoparticles brings novel properties into the resulting system, which would be entirely different from the properties of individual nanoparticles. This review presents an overview of current research in the area of anisotropic nanomaterials in general and noble metal nanoparticles in particular. We begin with an introduction to the advancements in this area followed by general aspects of the growth of anisotropic nanoparticles. Then we describe several important synthetic protocols for making anisotropic nanomaterials, followed by a summary of their assemblies, and conclude with major applications
Overproduction of salicylic acid in plants by bacterial transgenes enhances pathogen resistance
After a hypersensitive response to invading pathogens, plants show elevated accumulation of salicylic
acid (SA), induced expression of plant defense genes, and systemic acquired resistance (SAR) to further
infection by a broad range of pathogens. There is compelling evidence that SA plays a crucial role in triggering
SAR. We have transformed tobacco with two bacterial genes coding for enzymes that convert
chorismate into SA by a two-step process. When the two enzymes were targeted to the chloroplasts, the
transgenic (CSA, constitutive SA biosynthesis) plants showed a 500- to 1,000-fold increased accumulation
of SA and SA glucoside compared to control plants. Defense genes, particularly those encoding
acidic pathogenesis-related (PR) proteins, were constitutively expressed in CSA plants. This expression
did not affect the plant phenotype, but the CSA plants showed a resistance to viral and fungal infection resembling SAR in nontransgenic plants.Ministry of Economic Affairs, the Ministry of
Education, Culture and Science, and the Ministry of Agriculture, Nature
Management and Fishery in the framework of a research program of the
Association of Biotechnology Centres in the Netherlands (ABON)Peer reviewe
Gold nanorings synthesized via a stress-driven collapse and etching mechanism
10.1038/am.2016.163NPG Asia Materials811e32