[en] The emission current in a molybdenum field emission array can decrease by 50% in 1000 s at an oxygen pressure of 10^-6Torr. To overcome this disadvantage of molybdenum microtips, the effectiveness of dynamic surface cleaning has been investigated in a single-aperture gated-diode configuration. For dynamic surface cleaning, tip surface oxide buildup is balanced by tip oxide removal due to sputtering by ions created in ionizing collisions with field-emitted electrons. The present results demonstrate stable dynamic cleaning with clean and partially oxidized molybdenum tips for currents ranging from 10^-11 to 10^-9A with oxygen exposures of up to 1000 L. For currents above 10^-9A, ion bombardment causes the tip shape to become unstable leading to failure with increasing oxygen exposure. [copyright] 2001 American Institute of Physics

[en] This report describes the hydraulic testing programme performed during stage 3 of the site characterization and validation programme. It involved three separate components. Firstly, single borehole testing techniques (focused testing using equipment developed specifically for the Stripa poject) were used to determine the distribution of hydraulic conductivity and head in the C boreholes. Secondly, water was abstracted from boreholes which had been drilled to simulate a tunnel (simulated drift experiment - SDE). Locations and flow rates were measured together with pressure responses of points scattered through the SCV rock mass. Thirdly, the small scale crosshole (SSC) involved detailed hydraulic interference testing between the D holes and in the B and H zones to measure how hydraulic parameters such as transmissivity and storativity varied. (author)

[en] A brief discussion is given of the development and construction of a heavy ion source for heavy ion fusion

[en] A deuterium analog of doxepin was synthesized by the reduction of an N-doxepin carbamate with lithium aluminium deuteride. (Author)

[en] During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation, which is set to begin early in 2004, are now underway. The goal of the VENUS ECR ion source project as the RIA R and D injector is the production of 240emA of U30+, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5emA of U48+, a low current, very high charge state beam. During the commissioning phase with 18 GHz, tests with various gases and recently metals have been performed with up to 2000 W RF power and the performance is very promising. For example, 1100 e mu A of O6+,180 e mu A of Ar12+, 150 emA of Xe20+ and 100 emA of Bi24+ were produced in the early commissioning phase, ranking VENUS among the currently highest performance 18 GHz ECR ion sources. The emittance of the beams produced at 18 GHz was measured with a two axis emittance scanner. In FY04 a 10 kW, 28 GHz gyrotron system will be added, which will enable VENUS to reach full performance. The performance of the VENUS ion source, low energy beam transport (LEBT) and its closed loop cryogenic system are described in the paper. Recently, a new high temperature axial oven has been installed in the source and the first results on metal beams such as bismuth are given. The design of the 28 GHz, 10 kW gyrotron system is also be described. During the last year, the VENUS ECR ion source was commissioned at 18 GHz and preparations for 28 GHz operation, which is set to begin early in 2004, are now underway. The goal of the VENUS ECR+, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5 emA of U48+, a low current, very high charge state beam. During the commissioning phase with 18 GHz, tests with various gases and recently metals have been performed with up to 2000 W RF power and the performance is very promising. For example, 1100 e mu A of O6+, 180 e muA of Ar12+, 150 emA of Xe20+ and 100 emA of Bi24+ were produced in the early commissioning phase, ranking VENUS among the currently highest performance 18 GHz ECR ion sources. The emittance of the beams produced at 18 GHz was measured with a two axis emittance scanner. In FY04 a 10kW, 28 GHz gyrotron system will be added, which will enable VENUS to reach full performance. The performance of the VENUS ion source, low energy beam transport (LEBT) and its closed loop cryogenic system are described in the paper. Recently, a new high temperature axial oven has been installed in the source and the first results on metal beams such as bismuth are given. The design of the 28 GHz, 10 kW gyrotron system is also be described

[en] In 2001 the Queensland coal industry consolidated on record expansion in the export market over the past two years and again, increased its sales to overseas customers. New sales records were set in both the export and domestic markets. Unprecedented international demand for Queensland metallurgical coals coupled with improved prices and a favourable A$-US$ exchange rate created strong market conditions for the Queensland coal export industry, boosting confidence for further expansion and new developments. Australian coal exports in 2001 amounted to 194 Mt and are forecast to reach 275 million tonnes per annum (Mtpa) in 2020. The Queensland coal industry is poised to capture a significant share of this market growth. Queensland's large inventory of identified coal, currently estimated at more than 37 billion tonnes (raw coal m situ), is adequate to sustain the industry for many years and allow new opencut and underground mines to develop according to future market demand. Recent coal exploration successes are expected to add significant tonnage to the inventory (Coxhead, Smith and Coffey, 2002). Most of the coal exported from Queensland is mined in the Bowen Basin of central Queensland and additional tonnage of Walloon coal is exported by mines in the Moreton Basin and Surat Basin in south-east Queensland. The Walloon Coal Measures and its equivalents contain large resources of undeveloped opencut, high volatile, clean-burning thermal coal. The environmental advantages in the utilisation of these coals are now recognised and strong growth in production is expected in the near future for supply to both the domestic and export markets. Establishment of new rail transport and civil infrastructure will however, be required to support the development of large scale mining operations in this region

[en] The proton, carbon-13, and platinum-195 nuclear magnetic resonance spectra of some o-hydroxypyridinate-bridged dinuclear platinum(III) complexes have been analyzed and used to study some of their reactions. These complexes feature two Pt(III) ions joined by a metal-metal bond. Each Pt has two methyl groups on it in a cis configuration. Two hydroxpyridinate groups bridge the dinuclear unit. Derivatives of the parent compound have fluorine, chlorine, or a methyl group at the 6-position of the hydroxypyridinate. The bridging ligands may bind in head-to-head (HH) or head-to-tail (HT) arrangements. The HH complex has either a single pyridine or a single diethyl sulfide coordinated to the platinum ion to which the hydroxypyridinate oxygen atoms are also bound. In the HH complexes this ligand is in slow exchange with free ligand and binds at the sites coaxial to the metal-metal bond. For complexes with the bridging ligands hydroxypyridinate and 6-fluorohydroxypyridinate, increased pyridine concentration results in the isomerization of the ligand bridge to form HT complexes. The HT complexes have pyridine bound to both axial sites and in fast exchange with free pyridine at room temperature. The mechanism of the HH to HT rearrangement may involve a preequilibrium of the HH complex with pyridine. Rearrangement of the bridge is dissociative but does not involve complete dissociation from the complex. 14 refs., 1 fig., 6 tabs

[en] During the last year, the VENUS electron cyclotron resonance (ECR) ion source was commissioned at 18 GHz and preparations for 28 GHz operation, which is set to begin early in 2004, are now underway. The goal of the VENUS ECR ion source project as the RIA research and development injector is the production of 240 eμA of U³⁰⁺, a high current medium charge state beam. On the other hand, as an injector ion source for the 88-Inch Cyclotron the design objective is the production of 5 eμA of U⁴⁸⁺, a low current, very high charge state beam. During the commissioning phase with 18 GHz, tests with various gases and recently metals have been performed with up to 2000 W rf power and the performance is very promising. For example, 1100 eμA of O⁶⁺, 180 eμA of Ar¹²⁺, 150 eμA of Xe²⁰⁺, and 100 eμA of Bi²⁴⁺ were produced in the early commissioning phase, ranking VENUS among the currently highest performance 18 GHz ECR ion sources. The emittance of the beams produced at 18 GHz was measured with a two axis emittance scanner. In FY04 a 10 kW, 28 GHz gyrotron system will be added, which will enable VENUS to reach full performance. The performance of the VENUS ion source, low energy beam transport and its closed loop cryogenic system are described in the article. Recently, a high temperature axial oven has been installed in the source and the first results on metal beams such as bismuth are given. The design of the 28 GHz, 10 kW gyrotron system will also be described

[en] Stochastic Resonance (SR) occurs when the presence of noise in a nonlinear system can induce an optimal output from that system, and has been observed in a diverse range of physical and biological systems, including neurons. Despite this widespread observation of SR, to date very few engineering applications inspired by SR have been proposed, and one of the goals of our research is to explore possible new practical applications designed to replicate the benefits of SR. In particular, since about 1991, our group has designed and implemented a number of motion detection VLSI chips based on insect vision. We are currently investigating the possibility of replicating the benefits of SR in artificial insect-vision based motion detection systems, in particular a newly described form of SR called Suprathreshold Stochastic Resonance (SSR). The current paper is intended to review and identify the key open questions and avenues for future research relating to SR and SSR in such systems

[en] We report on the implementation of a microstructure comprising an array of micropillars to create a thin and stable film of nematic liquid crystal (LC), 5CB: 4'-pentyl-4-cyanobiphenyl, and the use of the microsystem for the colorimetric detection of vapor analytes. The microstructure uses capillary force generated by an array of cylindrical micropillars to steadily support a 22 µm thin film of LC, and overcomes susceptibility to gravity and shock. The feasibility of using the microsystem for gas phase detection is demonstrated by using dimethyl methylphosphonate (DMMP) gas to change the orientation of the LC and hence modulate the intensity of light transmitted through a crossed pair of polarizing films. The microstructure potentially offers a simple and portable solution to toxic gas detection. (brief communication)