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Octahedron-like \Au/\Fe3{\O}4 magnetic nanoparticles are synthesized using decomposition of FeO(OH) and \HAuCl4 with the presence of oleic acid in 1-octadecene solvent. In the octahedron-like hybrid particles, \Fe3{\O}4 mainly displayed the octahedral morphology and spherical Au nanoparticles partially embedded into one side of \Fe3{\O}4 octahedron. The size of particle could be tuned from 25  to 240 nm for the whole particle (mainly for \Fe3{\O}4) and 10  to 40 nm for Au by changing the proportion of the starting materials. The hybrid particles showed the magnetic properties of \Fe3{\O}4 with dependence on the size of \Fe3{\O}4 octahedron composite and the proportion of \Fe3{\O}4 to Au. Coercivity is observed in the hybrid \Au/\Fe3{\O}4 octahedron-like nanoparticles (55 Oe for 25 nm, 135 Oe for 100 nm, and 159 Oe for 240 nm) at room temperature. These size-controllable hybrid \Au/\Fe3{\O}4 magnetic octahedron-like particles, inheriting the advantages of Au and \Fe3{\O}4 nanoparticles, may evolve as useful building blocks for nano- and micro-electronic applications. [ABSTRACT FROM PUBLISHER]

Evaluates several techniques used to reduce the in-band phase noise contribution of ΔΣ (DS) fractional-N frequency synthesizers and develops several practical techniques for specifying the noise and linearity of components used in a DS fractional-N frequency synthesizers, as of November 2003. Highlights of such synthesizers used in this evaluation; Suitability of these synthesizers for resolving problems faced by radio system designers; Sources of in-band noise; Overview of the integrated circuit design used in this evaluation.

It is shown that, by using conventional VLSI design rules and device processing, a variety of two terminal and multiterminal integrated silicon light-emitting devices (Si-LEDs) can be routinely fabricated without any adaptation to the process, enabling the production of all-silicon monolithic optoelectronic systems. Their specific performance can be tailored by their different geometries and structures, yielding, by design, area, line, and point light-emitting patterns. The light-generating mechanisms are based on carrier quantum transitions in Si pn junctions, operated in the field emission or avalanche modes. Field emission Si-LEDs can operate at supply voltages compatible with those of integrated circuits (5 V or less). Avalanche Si-LEDs require higher operating voltages, but yield higher light intensities. The two terminal Si-LEDs yield a linear relation between the emitted light intensity and the driving current. The multiterminal Si-LEDs exhibit a nonlinear relation between the light emission intensity and the controlling electrical signal, enabling signal processing operations, which can not be attained in two terminal Si-LEDs. Two basic structures of multi terminal Si-LEDs are presented, i.e MOS-like structures, or carrier injection based structures (BJT-like devices). They possess different input impedances and both their emitted light intensities and emitting area patterns can be controlled by the input electrical signal. [ABSTRACT FROM PUBLISHER]

A novel experimental multiterminal silicon light emitting diode matrix is described, where both the emitted light intensity and the spatial light pattern of the device are controlled by insulated metal-oxide-semiconductor (MOS) gate voltages. It is found that the light intensity is a nonlinear quadratic function of the applied gate voltage. The nonlinear relationship enables, for example, the mixing of electrical input signals and modulation of the optical output signal, which can not readily be achieved with two terminal Si-light-emitting diodes, since they exhibit a linear relationship between diode avalanche current and light intensity [ABSTRACT FROM PUBLISHER]

Discusses the magnetic force calculation for permanent magnets using the Maxwell Stress Method. Consideration of magnetic force in the construction of permanent magnets; Significance of the calculation method to the structural design of the Alpha magnetic spectrometer flight magnet.