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Emissions and efficiency of a pellet boiler (40 kW) at nominal load were compared with emissions and efficiency at reduced load, while fired with six biomass pellets. The pellets include reed canary grass (Phalaris arundinacea), pectin waste from citrus shells (Citrus reticulata), sunflower husk (Helianthus annuus), peat, wheat straw (Triticum aestivum) and wood pellets. The measurements of emissions comprised of carbon monoxide (CO), nitrogen oxides (NO. x), sulphur oxides (SO. x) and flue dust mass concentrations (using DIN. plus and isokinetic sampling techniques). Emissions varied as a function of operational loads, for each type of pellets.The CO emissions were insignificant with reed canary grass (RCG), citrus pectin waste (CPW) and straw pellets at nominal load, however, at reduced load same pellets emitted 1.9, 4.0 and 7.4 times higher CO than wood pellets, respectively. Peat pellets emitted maximum CO at nominal load (4221.1 mgNm-3, 12.6 times higher than wood pellets) however; at reduced load CO emission was insignificant. The highest NOx emissions were reported with CPW, which were 3.4 and 4.6 times higher than wood pellets at nominal load and reduced load, respectively. Dust emissions were highest with sunflower husk and lowest with RCG pellets, at both operational modes. The best performance was reported with wood pellets, followed by RCG and pectin pellets, however, wood pellets combustion emitted 1.7 and 2.0 times higher dustDINplus than RCG at nominal and reduced loads, respectively. Not only fuel specific combustion optimization but also operational load specific optimization is essential for efficient use of agro-pellets in this type of boilers. © 2010 Elsevier Ltd.

Emissions from a multi-fuel domestic boiler (40 kW), fired with nine different agro-biomass pellets have been compared. The pellets include apple pomace (Malus domestica), reed canary grass (Phalaris arundinacea), pectin waste from citrus shells (Citrus reticulata), sunflower husk (Helianthus annuus), peat, two types of straw pellets and two types of wood pellets. The measurements of emissions comprised carbon monoxide (CO), nitrogen oxides (NOx), unburned hydrocarbons (CxHy), sulphur oxides (SOx) and flue dust mass concentration (by DINplus and isokinetic sampling methods). Comparison of experimental emission values with relevant quality labels (Blue Angel and Swan Mark) and standard (EN-303-5) showed that the boiler satisfied the emissions requirements of Blue Angel, Swan Mark and EN-303-5 when using wood pellets-1 (except CO emission), reed canary grass and citrus pectin waste pellets as fuel at nominal load. The wood pellets-1 yielded the highest boiler efficiency of 92.4%. Dusts emission varied as a function of fine content and elemental constituent of the pellets and was the highest with sunflower husk. CO and CxHy emissions were maximum with peat pellets. NOx emissions were below the concerned permissible values with all experimental pellets. Emissions of NOx and SOx were found maximum with straw pellets.For agro-pellets, statistical differences in ash contents were significant. High ash contents and low ash melting temperature made straw pellets less suitable for domestic applications. Reed canary grass, citrus pectin and apple pellets were the most suitable agro-pellets for small scale boilers with reasonable less ash contents and less emissions as compared to others. © 2010 Elsevier Ltd.

We report on observations of the blazar W Comae (ON+231) with the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE), a wavefront-sampling atmospheric Cherenkov telescope, in the spring of 2003. In a data set comprising 10.5 hours of ON-source observing time, we detect no significant emission from W Comae. We discuss the implications of our results in the context of the composition of the relativistic jet in W Comae, examining both leptonic and hadronic models for the jet. We derive 95% confidence level upper limits on the flux at the level of 1.5--3.5 x 10^{-10} cm^{-2} s^{-1} above 100 GeV for the leptonic models, or 0.5--1.1 x 10^{-10} cm^{-2} s^{-1} above 150 GeV for the hadronic models., Comment: 9 pages, 7 figures, uses emulateapj.sty. Accepted to ApJ

A subject seated in a modern vehicle (i.e., aircraft) and performing motor tasks may be submitted to inertial forces (Coriolis and centrifugal forces). These forces are sources of spatial disorientation, leading to perturbations of sensor-motor behaviour. The coding of the position of the head, which carries visual and vestibular sensors, is of particular interest with regards to this problem. We have investigated the influence of the position of the head on the accuracy of pointing movements towards visual memorized targets performed in a modified gravito-inertial field in to subjects seated 7Ocm off-centre on a platform rotating at 12O degrees/s. Subjects' head was either strongly immobilized in a vertical position (aligned with gravity vector) or completely free to move. Subjects were required to point as accurately as possible flashed visual targets presented in total darkness, before (PRE-rotation), during (PER-rotation) and after rotation of the platform (POST-rotation). Position of the head in the head free condition was recorded with an electromagnetic movement sensor (Polhemus Fastrack), whereas pointing accuracy as well as kinematics of the movements were recorded with an infrared position sensor device (Hamamatsu Motion Monitoring System)., The original document contains color images. Presented at the RTO Human Factors Symposium on Spatial Disorientation in Military Vehicles: Causes, Consquences and Cures, La Coruna, Spain, 15-17 Apr 2002, and published in RTO-MP-086. This article is from ADA413343 Spatial Disorientation in Military Vehicles: Causes, Consequences and Cures (Desorientation spaiale dans les vehicules militaires: causes, consequences et remedes)