Nachweis des Arsens

Ohne Zusammenfassung     

Microcapillary Supersonic Free-jet Injection: Plasma Diagnostics

Supersonic injection of a neutral, ground state gas through a microcapillary nozzle into a low density, weakly ionized, flowing plasma is employed to obtain information on the plasma characteristics. The “zone of silence” of the injected free-jet constitutes a pristine pocket of injected gas, adjustable in size by varying nozzle pressure and diameter of the injector. The shock waves bounding this region exclude massive particles yet transmit electrons, which excite the injected gas to yield radiative emission on lines specific to the gas. Other possible uses of microcapillary injection are discussed.     

Star Decompositions of Cubes

 Let S _k denote the complete bipartite graph K _{1, k} and let Q _n denote the n-cube. We prove that the obvious necessary conditions for the existence of an S _k -decomposition of Q _n are sufficient. Received: July 21, 1999 Final version received: May 16, 2000     

Comparing Theories of Infinite Resistive 1-Networks

Flanders' Hilbert space or finite power theory of infinite networks was extended to 1-networks by Zemanian. A new approach uses approximation by finite networks, a-priori bounds from no-gain properties, and Arzela–Ascoli, in a continuous function space. This paper compares, contrasts and reconciles these existence and uniqueness theories.     

Bijective proofs of two broken circuit theorems

We prove, by means of explicit bijections, theorems of Whitney and Stanley that express the coefficients of the chromatic polynomial of a graph G and the number of acyclic orientations of G in terms of numbers of sets of edges that contain no broken circuits of G.     

Finite element approximation of the Dirichlet problem using the boundary penalty method

Numerische Mathematik - This paper considers a finite element approximation of the Dirichlet problem for a second order self-adjoint elliptic equation,Au=f, in a region Ω ⊂ ℝn (n=2...     

An introduction to laser spectroscopy: Two cw-laser experiments

The principles, techniques and apparatus of two demonstration experiments using a tunable cw-laser are described. In the first experiment a passive external cavity enhanced the intensity of an incident laser beam enough to generate easily detected second harmonic UV radiation. The experiment also showed how to lock the frequency of one cavity to that of another. The second experiment used laser saturation spectroscopy to obtain sub-Doppler resolution and thereby exhibit the hyperfine spectrum of iodine molecules.