Fiber laser systems shine brightly

Describes the advancements in active fiber laser systems. Outline of cladding pumping technique for enhanced power scaling; Improved energies and peak powers; Extended wavelength range; Frequency doubling with fiber sources

Ulnar neuropathy at the elbow

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106702/1/mus24138.pd

Stretched pulse Yb³⁺:silica fibre laser

We report what we believe to be the first results on short-pulse generation in Yb3+:silica fiber. By applying the stretched pulse technique in a unidirectional, polarization-switch Yb3+ fiber laser incorporating a prism-based dispersive delay line, we obtain self-start mode locking and 100pJ pulses that can be compressed to give clean chirp-free <100fs pulses. We believe such sources to have great potential for use not only in all-solid-state high-power femtosecond pulse systems based on Yb3+:silica glass but also as seeds for conventional Nd3+:glass amplifier chains

Erbium fibre laser pumped nanosecond optical parametric oscillator

We report a periodically-poled lithium niobate optical parametric oscillator pumped by a frequency doubled Q-switched erbium-fibre laser. Pump tuning of the OPO signal with thresholds below 10µJ was demonstrated. Signal tuning range was 0.99-1.45µm

The Assessment of Communicative Competence in Aphasia

TB

A picosecond optical parametric oscillator synchronously pumped by an amplified gain-switched laser diode

We demonstrate a picosecond optical parametric oscillator synchronously pumped by a fiber-amplified gain-switched laser diode. Up to 7.3W at 1.54µm and 3.1W at 3.4µm is obtained at pulse repetition rates between 114.8 and 918.4MHz

Nanofiltration as Pretreatment to Reverse Osmosis for Paper and Pulp Mill Effluent

The paper and pulp industry produces effluent which is high in organic content and salinity, typically making is difficult to treat. For reclamation of this wastewater, the process should be designed such that the water is ‘fit for purpose’. Agricultural reuse of this waste stream is a potential option as the treatment requirements are less intense than for other reuse opportunities. This papers forms part of a larger project for developing an integrated UF-NF-RO system for reclaiming the biologically treated effluent from a thermo-mechanical pulp and paper mill in rural Australia. The current work has characterised the waste water and investigated a suite of commercially available NF membranes as a pre-treatment method for RO. Dead-end stirred cell filtration has been used to evaluate the selective removal of multivalent ions and low molecular weight organics in the NF stage. The result demonstrate the importance of the NF stage to the reclaimed water and show a SAR reduction of between 30-60% is achievable in this system. Of the commercially available membranes tested the membrane which performed the best was the NTR-7450 membrane from Hydranautics

Unsupervised system to classify SO2 pollutant concentrations in Salamanca, Mexico

Salamanca is cataloged as one of the most polluted cities in Mexico. In order to observe the behavior and clarify the influence of wind parameters on the Sulphur Dioxide (SO2) concentrations a Self-Organizing Maps (SOM) Neural Network have been implemented at three monitoring locations for the period from January 1 to December 31, 2006. The maximum and minimum daily values of SO2 concentrations measured during the year of 2006 were correlated with the wind parameters of the same period. The main advantages of the SOM Neural Network is that it allows to integrate data from different sensors and provide readily interpretation results. Especially, it is powerful mapping and classification tool, which others information in an easier way and facilitates the task of establishing an order of priority between the distinguished groups of concentrations depending on their need for further research or remediation actions in subsequent management steps. For each monitoring location, SOM classifications were evaluated with respect to pollution levels established by Health Authorities. The classification system can help to establish a better air quality monitoring methodology that is essential for assessing the effectiveness of imposed pollution controls, strategies, and facilitate the pollutants reduction