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Using Interracial Force Microscopy (IFM), we investigated the tribological behavior of hexadecanethiol monolayer on Au and films of octadecyltrichlorosilane (ODTS), perfluorodecyltrichlorosilane (PFTS) and dodecane on Si. We observe a strong correlation between hysteresis in a compression cycle (measured via nanoindentation) and friction. Additionally, we suggest that the amount of hysteresis and friction in each film is related to its detailed molecular structure, especially the degree of molecular packing.

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Residual, or unburned carbon in fly ash affects many aspects of power plant performance and economy including boiler efficiency, electrostatic precipitator operation, and ash as a salable byproduct. There is a large concern in industry on the unburned carbon problem due to a variety of factors, including low-NOx combustion system and internationalization of the coal market. In recent work, it has been found that residual carbon extracted from fly ash is much less reactive than the laboratory chars on which the current kinetics are based. It has been suggested that thermal deactivation at the peak temperature in combustion is a likely phenomenon and that the structural ordering is one key mechanism. The general phenomenon of carbon thermal annealing is well known, but there is a critical need for more data on the temperature and time scale of interest to combustion. In addition, high resolution transmission electron microscopy (HRTEM) fringe imaging, which provides a wealth of information on the nature and degree of crystallinity in carbon materials such as coal chars, has become available. Motivated by these new developments, this University Coal Research project has been initiated with the following goals: (1) To determine transient, high-temperature, thermal deactivation kinetics as a …

Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.

The increased demand for portable electronics has lead to the need for higher performance and efficiency. Devices operating at less than 50 {micro}W of power are defined as ultra-low-power (ULP) devices. New progress has been achieved on InP/InGaAs HBT and InAIAs/InGaAs HBT optimized for ULP applications. f{sub T} values of 2.2 GHz, and f{sub MAX} values of 20 GHz have been obtained for HBTs operating at less than 40 {micro}W. Current gain is greater than 45 with the device operating at less than 20 {micro}A on a 2.5 x 5 {micro}m{sup 2} device. These devices have been significantly improved over the previously reported MOCVD grown InP/InGaAs ULP HBT which has f{sub MAX} of 10 GHz operating in the ultra-low-power level. The improvements have been attributed to the reduction of base dopant diffusion associated with Zn doping.

The overall objective of this study was to determine if growth efficiency of young plantation loblolly pine and sweetgum can be maintained by intensive forest management and whether increased carbon gain is the mechanism controlling growth efficiency response to resource augmentation. Key leaf physiological processes were examined over two growing seasons in response to irrigation, fertigation (irrigation with a fertilizer solution), and fertigation plus pest control (pine only). Although irrigation improved leaf net photosynthesis in pine and decreased stomatal sensitivity to vapor pressure deficit in sweetgum, no consistent physiological responses to fertigation were detected in either species. After 4 years of treatment, a 3-fold increase in woody net primary productivity was observed in both species in response to fertigation. Trees supplemented with fertigation and fertigation plus pest control exhibited the largest increases in growth and biomass. Furthermore, growth efficiency was maintained by fertigation and fertigation plus pest control, despite large increases in crown development and self-shading. Greater growth in response to intensive culture was facilitated by significant gains in leaf mass and whole tree carbon gain rather than detectable increases in leaf level processes. Growth efficiency was not maintained by significant increases in leaf level carbon gain but was possibly …

The Main Injector (MI) supports the Tevatron Fixed Tar- get and Proton-Antiproton Collider modes of operation as well as providing 120 GeV/c resonantly extracted beam for the Main Injector Fixed Target Program. A set of beam transport lines, called Al and Pl, from the Main Injector converge on the injection point of the Tevatron, with the Al being used to transport 150 GeV/c antipro- tons (pbars) to the Tevatron. Pl is used to transport 150 GeV/c protons to the Tevatron, 120 GeV/c protons to the pbar target, and eventually 120 GeV/c resonantly ex- tracted protons to the existing Fixed Target areas. In ad- dition, the Pl line will be used to transport 8.9 GeV/c pbars from the Source back to the MI and recycled 150 GeV/c pbars at the end of Collider stores. In order to ac- complish the second and third function, the Pl beamline is continued beyond the Tevatron injection point in a sec- tion of the decommissioned Main Ring, called the P2 beamline. This transports the protons to a magnetic switch used to select either the modified transport line, used for targeting protons for pbar production, or the transport line which connects to the existing Fixed Target …

The mysterious dark matter has been a subject of special interest to high energy physicists, astrophysicists and cosmologists for many years. According to theoretical models, it can make up a significant fraction of the mass of the Universe. One possible form of galactic dark matter, Weakly Interacting Massive Particles (WIMPs), could be detected by their annihilation into monoenergetic gamma-ray line(s). This paper will demonstrate that the Gamma-ray Large Area Space Telescope (GLAST), scheduled for launch in 2005 by NASA, will be capable of searching for these gamma-ray lines in the energy range from 20 GeV to {approx}500 GeV and will be sufficiently sensitive to test a number of models. The required instrument performance and its capability to reject backgrounds to the required levels are explicitly discussed.

This project has comprised design, analysis, laboratory testing, and field testing of insulated drill pipe (IDP). This paper will briefly describe the earlier work, but will focus on results from the recently-completed field test in a geothermal well. Field test results are consistent with earlier analyses and laboratory tests, all of which support the conclusion that insulated drill pipe can have a very significant effect on circulating fluid temperatures. This will enable the use of downhole motors and steering tools in hot wells, and will reduce corrosion, deterioration of drilling fluids, and heat-induced failures in other downhole components.

Laboratory experiments have been performed to evaluate the performance of a premixed low-swirl burner (LSB) in configurations that simulate commercial heating appliances. Laser diagnostics were used to investigate changes in flame stabilization mechanism, flowfield, and flame stability when the LSB flame was confined within quartz cylinders of various diameters and end constrictions. The LSB adapted well to enclosures without generating flame oscillations and the stabilization mechanism remained unchanged. The feasibility of using the LSB as a low NO{sub x} commercial burner has also been verified in a laboratory test station that simulates the operation of a water heater. It was determined that the LSB can generate NO{sub x} emissions < 10 ppm (at 3% O{sub 2}) without significant effect on the thermal efficiency of the conventional system. The study has demonstrated that the lean premixed LSB has commercial potential for use as a simple economical and versatile burner for many low emission gas appliances.

The authors report spurious free dynamic range measurements of 850nm vertical cavity surface emitting lasers in short multimode links for radio frequency communication. For a 27m fiber link, the dynamic range at optimal bias was greater than 95dB-Hz{sup 2/3} for modulation frequencies between 1 and 5.5 GHz, which exceeds the requirements for antenna remoting in microcellular networks. In a free space link, they have measured the highest dynamic range in an 850nm vertical cavity surface emitting laser of 113dB-Hz{sup 2/3} at 900MHz. We have also investigated the effects of modal noise and differential mode delay on the dynamic range for longer lengths of fiber.

Ernest Orland Lawrence Berkeley National Laboratory (Berkeley Lab) is the oldest of America's national laboratories and has been a leader in science and engineering technology for more than 65 years, serving as a powerful resource to meet Us national needs. As a multi-program Department of Energy laboratory, Berkeley Lab is dedicated to performing leading edge research in the biological, physical, materials, chemical, energy, environmental and computing sciences. Ernest Orlando Lawrence, the Lab's founder and the first of its nine Nobel prize winners, invented the cyclotron, which led to a Golden Age of particle physics and revolutionary discoveries about the nature of the universe. To this day, the Lab remains a world center for accelerator and detector innovation and design. The Lab is the birthplace of nuclear medicine and the cradle of invention for medical imaging. In the field of heart disease, Lab researchers were the first to isolate lipoproteins and the first to determine that the ratio of high density to low density lipoproteins is a strong indicator of heart disease risk. The demise of the dinosaurs--the revelation that they had been killed off by a massive comet or asteroid that had slammed into the Earth--was a theory developed here. …

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Extreme Ultraviolet Lithography (EUVL) has emerged as one of the leading successors to optics for 0.1 {micro}m IC fabrication. Its strongest attribute is the potential to scale to much finer resolution at high throughput. As such, this technique could meet the lithography needs for Si ULSI down to fundamental device limits. In the US, Lawrence Livermore, Sandia, and Lawrence Berkeley National Laboratories are participating in an industry funded research effort to evolve EUV technology and build a prototype camera for lithographic exposure. More recently, both Europe and Japan have initiated government/industry sponsored programs in EUVL development. This talk will focus on our program successes to date, and highlight some of the challenges that still lie ahead.

We describe the microfabrication of an extremely compact optical system as a key element in an integrated capillary channel electrochromatograph with fluorescence detection. The optical system consists of a vertical cavity surface-emitting laser (VCSEL), two high performance microlenses and a commercial photodetector. The microlenses are multilevel diffractive optics patterned by electron beam lithography and etched by reactive ion etching in fused silica. The design uses substrate-mode propagation within the fused silica substrate. Two generations of optical subsystems are described. The first generation design has a 6 mm optical length and is integrated directly onto the capillary channel-containing substrate. The second generation design separates the optical system onto its own substrate module and the optical path length is further compressed to 3.5 mm. The first generation design has been tested using direct fluorescence detection with a 750 nm VCSEL pumping a 10{sup {minus}4}M solution of CY-7 dye. The observed signal-to-noise ratio of better than 100:1 demonstrates that the background signal from scattered pump light is low despite the compact size of the optical system and is adequate for system sensitivity requirements.

A mechanically-induced color transition (''mechanochromism'') in polydiacetylene thin films has been generated at the nanometer scale using the tips of two different scanning probe microscopes. A blue-to-red chromatic transition in polydiacetylene molecular trilayer films, polymerized from 10,12-pentacosadiynoic acid (poly-PCDA), was found to result from shear forces acting between the tip and the poly-PCDA molecules, as independently observed with near-field scanning optical microscopy and atomic force microscopy (AFM). Red domains were identified by a fluorescence emission signature. Transformed regions as small as 30 nm in width were observed with AFM. The irreversibly transformed domains preferentially grow along the polymer backbone direction. Significant rearrangement of poly-PCDA bilayer segments is observed by AFM in transformed regions. The removal of these segments appears to be a characteristic feature of the transition. To our knowledge, this is the first observation of nanometer-scale mechanochromism in any material.

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO examined the General Services Administration's (GSA) retail packaging products program, focusing on whether: (1) GSA is required by law to set its prices for retail packaging products at levels sufficient to ensure that all selling costs are recovered on each item; and (2) GSA's selling prices for these items do recover all costs."

The Geothermal Drilling Organization (GDO), founded in 1982 as a joint Department of Energy (DOE)-Industry organization, develops and funds near-term technology development projects for reducing geothermal drilling costs. Sandia National Laboratories administers DOE funds to assist industry critical cost-shared projects and provides development support for each project. GDO assistance to industry is vital in developing products and procedures to lower drilling costs, in part, because the geothermal industry is small and represents a limited market.

The Instrumented Flux Return (IFR)[1] is one of the five subdetectors of the BaBar[2] experiment on the PEP II accelerator at SLAC. The IFR consists of 774 Resistive Plate Chamber (RPC) detectors, covering an area of about 2,000 m{sup 2} and equipped with 3,000 Front-end Electronic Cards (FEC) reading about 50,000 channels (readout strips). The first aim of a B-factory experiment is to run continuously without any interruption and then the Detector Control system plays a very important role in order to reduce the dead-time due to the hardware problems. The I.N.F.N. group of Naples has designed and built the IFR Online Detector Control System (IODC)[3] in order to control and monitor the operation of this large number of detectors and of all the IFR subsystems: High Voltage, Low Voltage, Gas system, Trigger and DAQ crates. The IODC consists of 8 custom DAQ stations, placed around the detector and one central DAQ station based on VME technology and placed in electronic house. The IODC use VxWorks and EPICS to implement slow control data flow of about 2500 hardware channels and to develop part of the readout module consisting in about 3500 records. EPICS is interfaced with the BaBar Run Control …

Weekly newspaper from Cleveland, Texas that includes local, county, and state news along with extensive advertising.

Semiweekly newspaper from Levelland, Texas that includes local, state, and national news along with advertising.