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The enormous amount of wastes produced during wood processing operations in many countries provides challenging opportunities for the use of wood waste as a construction material. In this research, wood waste (sawdust and wood shaving) ash (WWA) of pretreated timber of 0, 5, 10, 15, 20, 25, and 30% by weight of cement was added as a supplement to a concrete of mix proportion 1:2:4:0.56 (cement:sand:coarse aggregate:water cement ratio), and the strengths and the water absorption of the matrix were evaluated. Also, the metal leachability of WWA was analyzed. The compressive and the flexural strengths of WWA concrete for the ages investigated ranged from 12.83 to 28.66 N/[mm.sup.2], and 3.65 to 5.57 N/[mm.sup.2], respectively, with the lowest values obtained at 30% additive level of ash. When compared with the strength of plain concrete (control), the compressive and flexural strengths of WWA concrete were between 62 and 91% and 65 and 98%, respectively, of the former. The trend of the water absorption of WWA concrete was a reversal of those of the strengths, that is, the highest water absorption values were recorded for concrete specimens with the highest additive level of ash. A batch leaching test also performed at an ash-leachant volumetric ratio of 20 produced leachate containing chromium, arsenic, iron, copper, and zinc at the following concentrations: 410, 6720, 150, 280, and 1690 [micro]g/L, respectively, when leached at a pH of 4, and 400, 10,670, 0, 100, 1470 [micro]g/L, respectively, when leached at a pH of 5. These concentration levels exceed the EPA fresh water acute criteria limits. CE Database subject headings: Wood; Ashes; Compressive strength; Flexural strength; Heavy metals; Recycling; Concrete.

The Cassini spacecraft Ultraviolet Imaging Spectrograph (UVIS) obtained observations of Jupiter's auroral emissions in [H.sub.2] band systems and H Lyman-[alpha] from day 275 of 2000 (October 1), to day 81 of 2001 (March 22). Much of the globally integrated auroral variability measured with UVIS can be explained simply in terms of the rotation of Jupiter's main auroral arcs with the planet. These arcs were also imaged by the Space Telescope Imaging Spectrograph (STIS) on Hubble Space Telescope (HST). However, several brightening events were seen by UVIS in which the global auroral output increased by a factor of 2-4. These events persisted over a number of hours and in one case can clearly be tied to a large solar coronal mass ejection event. The auroral UV emissions from these bursts also correspond to hectometric radio emission (0.5-16 MHz) increases reported by the Galileo Plasma Wave Spectrometer (PWS) and Cassini Radio and Plasma Wave Spectrometer (RPWS) experiments. In general, the hectometric radio data vary differently with longitude than the UV data because of radio wave beaming effects. The 2 largest events in the UVIS data were on 2000 day 280 (October 6) and on 2000 days 325-326 (November 20-21). The global brightening events on November 20-21 are compared with corresponding data on the interplanetary magnetic field, solar wind conditions, and energetic particle environment. ACE (Advanced Composition Explorer) solar wind data was numerically propagated from the Earth to Jupiter with an MHD code and compared to the observed event. A second class of brief auroral brightening events seen in HST (and probably UVIS) data that last for ~2 min is associated with auroral flares inside the main auroral ovals. On January 8, 2001, from 18:45-19:35 UT UVIS [H.sub.2] band emissions from the north polar region varied quasiperiodically. The varying emissions, probably due to auroral flares inside the main auroral oval, are correlated with low-frequency quasiperiodic radio bursts in the 0.6-5 kHz Galileo PWS data. Keywords: Auroras; Jupiter; Solar wind; Ultraviolet

Enceladus makes its mark on Saturn Despite considerable differences between the magnetospheres of Saturn and Jupiter, cryovolcanic activity on Saturn's icy moon Enceladus was suspected to connect the moon to Saturn in a similar way to the electrodynamic coupling seen between Jupiter and its Galilean moons. This suspicion has been confirmed. Analysis of data collected during a Cassini fly-by within 55 kilometres of Enceladus in August 2008 reveals magnetic field-aligned ion and electron beam emissions from Enceladus with sufficient power to stimulate detectable aurora. Subsequent observations with the Cassini ultraviolet imaging spectrometer system detected the expected Enceladus auroral footprint in Saturn's atmosphere. Although there are substantial differences between the magnetospheres of Jupiter and Saturn, it has been suggested that cryovolcanic activity at Enceladus.sup.1,2,3,4,5,6,7,8,9 could lead to electrodynamic coupling between Enceladus and Saturn like that which links Jupiter with Io, Europa and Ganymede. Powerful field-aligned electron beams associated with the Io-Jupiter coupling, for example, create an auroral footprint in Jupiter's ionosphere.sup.10,11. Auroral ultraviolet emission associated with Enceladus-Saturn coupling is anticipated to be just a few tenths of a kilorayleigh (ref. 12), about an order of magnitude dimmer than Io's footprint and below the observable threshold, consistent with its non-detection.sup.13. Here we report the detection of magnetic-field-aligned ion and electron beams (offset several moon radii downstream from Enceladus) with sufficient power to stimulate detectable aurora, and the subsequent discovery of Enceladus-associated aurora in a few per cent of the scans of the moon's footprint. The footprint varies in emission magnitude more than can plausibly be explained by changes in magnetospheric parameters--and as such is probably indicative of variable plume activity., Author(s): Wayne R. Pryor [sup.1] [sup.2] , Abigail M. Rymer [sup.3] , Donald G. Mitchell [sup.3] , Thomas W. Hill [sup.4] , David T. Young [sup.5] , Joachim Saur [sup.6] [...]