Documento di orientamento del gruppo di lavoro del comitato scientifico di DPI -Italia Onlus (2012-2018) La definizione dei servizi di sostegno alla partecipazione e all’inclusione alla luce della UNCRPD

Documento di orientamento del gruppodi lavoro del comitato scientificodi DPI -Italia Onlus (2012-2018)La definizione dei servizi di sostegnoalla partecipazione e all’inclusione alla lucedella UNCRP

A new shock tube configuration for studying dust-lifting during the initiation of a coal dust explosion

The traditional defence against propagating coal dust explosions is the application of dry stone dust. This proven and effective safety measure is strictly regulated based on extensive international experience. While new products, such as foamed stone dust, offer significant practical benefits, no benchmark tests currently exist to certify their dust lifting performance in comparison to dry stone dust. This paper reviews the coal dust explosion mechanism, and argues that benchmark testing should focus on dust lifting during the initial development of the explosion, prior to arrival of the flame. In a practical context, this requires the generation of shock waves with Mach numbers ranging from 1.05 to 1.4, and test times of the order of 10’s to 100’s of milliseconds. These proposed test times are significantly longer than previous laboratory studies, however, for certification purposes, it is argued that the dust lifting behaviour should be examined over the full timescales of an actual explosion scenario. These conditions can be accurately targeted using a shock tube at length scales of approximately 50 m. It is further proposed that useful test time can be maximised if an appropriately sized orifice plate is fitted to the tube exit, an arrangement which also offers practical advantages for testing. The paper demonstrates this operating capability with proof-of-concept experiments using The University of Queensland’s X3 impulse facility

Conservation status of oyster reef ecosystem of Southern and Eastern Australia

Reef ecosystems all over the world are in decline and managers urgently need information that can assess management interventions and set national conservation targets. We assess the conservation status and risk of ecosystem collapse for the Oyster Reef Ecosystem of Southern and Eastern Australia, which comprises two community sub-types established by Saccostrea glomerata (Sydney rock oyster) and Ostrea angasi (Australian flat oyster), consistent with the IUCN Red List of Ecosystems risk assessment process. We established: (i) key aspects of the ecosystem including: ecological description, biological characteristics, condition and collapse thresholds, natural and threatening processes; (ii) previous and current extent of occurrence and current area of occupancy; and (iii) its likelihood of collapse within the next 50e100 years. The most severe risk rating occurred for Criterion A: Reduction in Extent (since 1750) and Criterion D: Disruption of biotic processes (since 1750), although assessment varied from Least Concern to Critically Endangered amongst the four criteria assessed. Our overall assessment ranks the risk of collapse for the ecosystem (including both community sub-types) as Critically Endangered with a high degree of confidence. Our results suggest the need for rapid intervention to protect remaining reefs and undertake restoration at suitable sites. Several restoration projects have already demonstrated this is feasible, and Australia is well equipped with government policies and regulatory mechanisms to support the future conservation and recovery of temperate oyster ecosystems

Mining Modification of River Systems: A case study from the Australian Gold Rush

Mobilisation of large volumes of bedrock, regolith and soil has long been a characteristic feature of metal mining. Prior to the 20th century this was most efficiently achieved through harnessing the motive power of water. Large-scale water use in mining produced waste sands, gravels and silts that were flushed downstream, triggering changes in stream and floodplain morphology and function. During the 19th century the shift from artisanal to industrialised mining resulted in a rapid increase in the scale and extent of environmental change. This paper presents results from a multi-disciplinary research program investigating the environmental effects of 19th-century gold mining on waterways in south-eastern Australia. Archaeological and geospatial landscape survey are combined with historical data modelling and geomorphological analysis to examine the extractive processes that produced sediment in headwater regions and how this influenced fluvial processes operating on downstream waterways and floodplains. Our case study of the Three Mile-Hodgson Creek system on the Ovens (Beechworth) goldfield in north-east Victoria indicates that miners mobilised up to 7.3 million m3 of sediment in this small catchment alone. Results of the research suggest that tailings dams and sludge channels in this catchment are important archaeological evidence for early attempts to manage industrial waste

ON THE CANONICAL FORMATION OF CERTAIN SECOND-ORDER PARTIAL DIFFERENTIAL DIFFERENTIAL EQUATIONS IN A TYPE PRESERVING FIELD

Describes the canonical representation of some second-order partial differential equations in a type-preserving domain

Early plantation growth and tolerance to ramularia shoot blight of provenances of three spotted gum taxa on a range of sites in Queensland

Early height growth and field tolerance to Quambalaria pitereka, the casual agent of ramularia shoot blight, were assessed for eleven provenances of Corymbia citriodora ssp. variegata, nine provenances of C. citriodora ssp. citriodora and eight provenances of C. henryi, within existing trials involving 22 diverse sites in Queensland. Not all taxa and provenances were present at all sites. The age at assessment varied, but was primarily between 10 and 21 mo. Assessments indicated that ramularia shoot blight at a specific site was closely associated with local climatic conditions, with mean annual rainfall being a useful indicator of the potential disease risk. It also appears that the mean annual rainfall at the origin of the provenance is a good indicator of the potential tolerance of the provenance to ramularia shoot blight, with the most tolerant provenances of all three spotted gum taxa originating from sites with more than 1000 mm. Of the taxa and provenances tested, the Woondum provenance of C. citriodora ssp. variegata has consistently demonstrated good growth rates and high tolerance to ramularia shoot blight across a wide range of sites. It is recommended that this provenance or other similarly tolerant provenances be selected for use in all future C. citriodora ssp. variegata plantations in southern Queensland where annual rainfall exceeds 800 mm. For C. citriodora ssp. citriodora, the Herberton and Kirrama provenances demonstrated good growth rates and high tolerance to ramularia shoot blight across a range of sites. For C. henryi there was little difference between provenances in growth or tolerance to ramularia shoot blight. While general tolerance was low, some good individuals were observed in the Gold Coast and Myrtle Creek provenances. The results presented in this paper provide guidance towards provenance selection for plantation establishment and on-going tree improvement for the three spotted gum taxa. It is anticipated that within a few years increasing quantities of seed from commercial seed orchards will become available, giving plantation growers a seed supply with considerably greater growth potential and tolerance of ramularia shoot blight than any source currently available from natural provenances. Keywords: provenance trials; disease prevalence; tolerance; susceptibility; spotted gum; Corymbia citriodora ssp. citriodora; Corymbia citriodora ssp. variegata; Corymbia henryi; ramularia shoot blight; Quambalaria pitereka; Queenslan