Abstract: A new type of atom guiding structure has been analyzed. It consists of a low-core optical fiber (step-index) which is not clad, but instead has a metal coating on its outer lateral surface. It will be shown that this structure produces the maximum evanescent field in the hollow region of the fiber and guiding can be accomplished with lower power lasers. Both the dipole and the vander Waals potentials have been combined and the resulting barrier height was maximized as a function of both .DELTA., the detuning, and r, the position. An optimized potential having a barrier height of 1 K has been determined by iteratively solving for the required laser intensity. The probability of atoms tunneling through this barrier to the inner wall has been calculated and is expected to be unimportant. Centripetal effects due to a bending of the fiber have also been estimated and are small for the barrier considered here.

Abstract: Polymer materials having a low Young's modulus, a low dielectric constant, and a high apparent piezoelectric response when subjected to a high direct bias voltage and a superimposed alternating voltage, used as the active element in an underwater acoustic signal projector of a sonar system.

Abstract: A broadband, traveling wave amplifier which includes a target anode and an lectron gun for bombarding the anode with an electron beam having an amplitude proportional to that of an input signal. The electron gun includes a NEA semiconductor cold cathode having an electron emitting surface and a modulation structure for modulating the emitted electron beam with an input signal to be amplified. The electron gun and the anode are configured as parallel strip transmission lines having the same phase velocity. The target anode may be a reversed-biased stripline diode, Schottky barrier stripline diode, or metal/semiconductor/metal stripline structure.

Abstract: There is disclosed a digital frequency synthesizer which converts an ultrnic burst from an echo-ranging sonar system into a continuous signal having a frequency exactly equal to the frequency of the cycles making up the burst. This burst is detected and a number representing the period of this burst generated and transmitted to a first counter. A clock pulse train is generated and transmitted to a second counter. When the numbers in the first and second counters coincide, a single output pulse is generated and the second counter reset. When this cycle is repeated, the frequency of the resultant pulse train reflects any change in frequency of the cycles making up the bursts.

Abstract: A spark plug having a positive electrode spark tip which is covered with a ery thin layer (.ltoreq.20 nanometers) of very hard NEA material having very large chemical binding energies such that most elements, including carbon and nitrogen, will not bind to its surface. The NEA material may be sapphire, or may be an n-type impurity-doped semiconductor material such as n-type AlN, cBN, or GaAlN having a bandgap exceeding 5.5 eV.

Abstract: A light-weight, liquid-blocking ring assembly for a surface drain for preventing a harmful liquid spilled nearby from entering the drain, which can be quickly and easily installed by a single person, and includes positive verification that none of the undesired liquid has entered the drain. The assembly includes (1) a center portion having a latching mechanism for attaching and drawing the assembly towards the drain, (2) a peripheral band which surrounds and is spaced from the drain, and which carries at its bottom edge a resilient gasket conformable to the surface surrounding the drain, and (3) an intermediate structure connecting the center portion and the peripheral band without blocking a clear view of the entire surface surrounding the drain.

Abstract: Second-order nonlinear optical polymeric films, including alternating monlecular layers of two head-to-head, mainchain, amphophilic, chromophoric polymers, one polymer having the electron donating end of the chromophore attached to hydrophilic groups, and the other polymer having the electron donating end of the chromophore attached to hydrophobic groups, and methods of fabricating the films for use in optonics.

Abstract: A method of detecting/identifying organic molecules which have been mixed th an appropriate electrolyte to form an electrolytic solution is disclosed. The organic molecules to be detected/identified are adsorbed onto the surface of a conducting substrate, which is adjusted to an overall positive voltage potential within a range of E.sub.LOW and E.sub.HIGH. The voltage potential on the surface of the conducting substrate, and, accordingly, the adsorbed organic molecules, is adjusted until an electrochemically-induced change occurs. The voltage potential at which the change occurs is characteristic of the organic molecule, thus permitting detection/identification thereof.

Abstract: An apparatus for and a method of on-line detecting and assessing, in situ, he amount and characterization of microbial trace contamination in an associated ultra-pure water system is disclosed. The apparatus comprises, inter alia, a monitor/detector portion and an assessment/identification portion. The monitor/detector portion includes a contamination mass detector which nondestructively senses the presence of microbial biofilms in real time when grown upon the surface of a quartz crystal wafer portion of the contamination mass detector. The assessment/identification portion is configured to provide quantitative analysis of the microbial biofilms formations based on signature biomarker cellular components. A programmable controller is configured to integrate these and other portions into an automated apparatus, which is capable of providing real time chemical countermeasures to prevent the potential deleterious effect of the microbial trace contamination uncovered.

Abstract: Light at known angles is impinged onto an object whose contour is to be mured and a camera is used to receive the reflected light which is then recorded. A computer processes the images, mathematically manipulating them so that surface slopes are known. The slopes are than integrated to obtain local elevations which represent the object contour.

Abstract: A method of growing a large single crystalline diamond film, in which a nickel substrate is disposed within a diamond growth chamber. After air has been evacuated from the chamber and the substrate has been heated to a temperature exceeding 1145 Celsius, atomic hydrogen is continuously generated from hydrogen gas supplied to the chamber and accelerated toward the substrate, implanting hydrogen atoms in the top substrate surface and converting it to a liquid film of nickel hydride. Then one of two layers of diamond particles of two to three nanometer cross section is deposited on the liquid nickel hydride film, whereby the diamond particles arrange themselves on the liquid nickel hydride film to their lowest free energy state, forming a nascent contiguous single-crystalline diamond film. Thereafter diamond is homoepitaxially grown on the nascent contiguous single-crystalline diamond film to the desired thickness.

Abstract: A method of synthesizing a large area, single crystalline, semiconductor wafer in which the semiconductor is grown on a substrate having a lower melting temperature and higher specific gravity than the overlying semiconductor. The substrate is disposed within an open container or holder having a drain plug. First, a very thin layer of semiconductor is grown on the substrate. Then, the temperature is raised to melt the substrate and anneal the very thin layer of semiconductor. Next, growth of the semiconductor film now floating on the molten substrate is resumed until the desired thickness is obtained. Then, the molten substrate is drained from the holder, the temperature lowered to room temperature, and the nascent large area semiconductor wafer removed from the holder.

Abstract: A vertically integrated DRAM cell having a storage time of at least 4.5 hours at room temperature, formed from a wide-bandgap semiconductor such as GaAs or AlGaAs, in which an n-p-n bipolar access transistor is merged with a p-n-p storage capacitor, with the middle p-n layers being common to both. Similarly, a p-n-p transistor can be merged with an n-p-n storage capacitor.

Abstract: An evaporation method of producing a new high Tc superconducting material using fullerene molecules as artificial pinning sites for any magnetic flux that may enter the material.

Abstract: A process for forming a copper alloy which is strengthened while maintaining good electrical and thermal conductivity by the addition of TiN or ZrN consists of external nitridation of a mechanically alloyed powder mixture followed by further mechanical alloying to break down the surface coating which forms during nitridation.

Abstract: Protective fairings which can be easily added to existing unfaired underwr sensor line arrays or incorporated into new faired underwater sensor line arrays to provide shock and impact protection to array sensors and cables without degradation of sensor output and allow the line array to be repeatedly raised and lowered under tension from a ship and stored on the ship without disassembly.

Abstract: A piezoelectric composite which can be used as a transducer is constructed of parallel piezoelectric ceramic rods set in a passive polymer matrix which has a negative Poisson ratio whereby the electromechanical coupling of the transducer is greatly increased.

Abstract: A semiconductor cold electron emission device comprising a type I heterojunction formed of a P-type semiconductor mixture of AlN and a N-type semiconductor mixture of SiC which junction is forward biased so that electrons are monoenergetically emitted from the P-type semiconductor mixture.

Abstract: A method of producing a new high Tc superconducting material using fullerene molecules as artificial pinning sites for any magnetic flux that may enter the material.

Abstract: A heterojunction bipolar transistor (HBT) structure is configured so that the heterojunction between hexagonal and cubic materials is electrically active. A first embodiment of the HBT structure comprises both hexagonal and cubic silicon carbide (SiC). The emitter region is fabricated from the higher bandgap hexagonal SiC appropriately doped. The base and collector regions are grown using the lower bandgap cubic SiC. A second embodiment of the HBT structure comprises both a solid solution of SiC material such as an alloy of silicon carbon aluminum nitrogen (SiCAlN) grown upon a substrate of hexagonal SiC. The emitter region can be placed either on the top or bottom of the second embodiment of the HBT structure. Also, the bandgap between the emitter and base regions of the second embodiment can be varied by controlling the mole fraction ratio between the constituent parts of the SiCAlN, i.e., between the SiC and the AlN.