National Physical Laboratory

About: National Physical Laboratory is a facility organization based out in London, United Kingdom. It is known for research contribution in the topics: Dielectric & Thin film. The organization has 7615 authors who have published 13327 publications receiving 319381 citations.

The Asymptotic Solution of Linear Differential Equations of the Second Order for Large Values of a Parameter

Abstract: Asymptotic solutions of the differential equations d2w/dz2 = {uzn +f{z)} w 0, 1) for large positive values of u, have the formal expansions P(z) 1+ Z5=1 (f> l+ ^ M y us s 5=0 IIs where P is an exponential or Airy function for n 0 or 1 respectively. The coefficients A s (z) and B s (z) are given by recurrence relations. This paper proves that solutions of the differential equations exist whose asymptotic expansions in Poincare’s sense are given by these series, and that the expansions are uniformly valid with respect to the complex variable z. The method of proof differs from those of earlier writers and fewer restrictions are made.

Non-volatile photochemical gating of an epitaxial graphene/polymer heterostructure.

Abstract: A novel heterostructure based on epitaxial graphene grown on silicon carbide combined with two polymers is demonstrated, with a neutral spacer and a photoactive layer that provides potent electron acceptors under UV light exposure. UV exposure of this heterostructure enables control of the electrical parameters of graphene in a non-invasive, non-volatile, and reversible way.

Functionalized Multilayered Graphene Platform for Urea Sensor

Abstract: Multilayered graphene (MLG) is an interesting material for electrochemical sensing and biosensing because of its very large 2D electrical conductivity and large surface area. We propose a less toxic, reproducible, and easy method for producing functionalized multilayer graphene from multiwalled carbon nanotubes (MWCNTs) in mass scale using only concentrated H2SO4/HNO3. Electron microscopy results show the MLG formation, whereas FTIR and XPS data suggest its carboxylic and hydroxyl-functionalized nature. We utilize this functionalized MLG for the fabrication of a novel amperometric urea biosensor. This biosensor shows linearity of 10–100 mg dL–1, sensitivity of 5.43 μA mg–1 dL cm–2, lower detection limit of 3.9 mg dL–1, and response time of 10 s. Our results suggest that MLG is a promising material for electrochemical biosensing applications.

Industrial Applications of Terahertz Sensing: State of Play.

Abstract: This paper is a survey of existing and upcoming industrial applications of terahertz technologies, comprising sections on polymers, paint and coatings, pharmaceuticals, electronics, petrochemicals, gas sensing, and paper and wood industries. Finally, an estimate of the market size and growth rates is given, as obtained from a comparison of market reports.