992 resultados para mine water


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Zanazziite is the magnesium member of a complex beryllium calcium phosphate mineral group named roscherite. The studied samples were collected from the Ponte do Piauí mine, located in Itinga, Minas Gerais. The mineral was studied by electron microprobe, Raman and infrared spectroscopy. The chemical formula can be expressed as Ca2.00(Mg3.15,Fe0.78,Mn0.16,Zn0.01,Al0.26,Ca0.14)Be4.00(PO4)6.09(OH)4.00⋅5.69(H2O) and shows an intermediate member of the zanazziite–greinfeinstenite series, with predominance of zanazziite member. The molecular structure of the mineral zanazziite has been determined using a combination of Raman and infrared spectroscopy. A very intense Raman band at 970 cm−1 is assigned to the phosphate symmetric stretching mode whilst the Raman bands at 1007, 1047, 1064 and 1096 cm−1 are attributed to the phosphate antisymmetric stretching mode. The infrared spectrum is broad and the antisymmetric stretching bands are prominent. Raman bands at 559, 568, 589 cm−1 are assigned to the ν4 out of plane bending modes of the PO4 and HPO4 units. The observation of multiple bands supports the concept that the symmetry of the phosphate unit in the zanazziite structure is reduced in symmetry. Raman bands at 3437 and 3447 cm−1 are attributed to the OH stretching vibrations; Raman bands at 3098 and 3256 are attributed to water stretching vibrations. The width and complexity of the infrared spectral profile in contrast to the well resolved Raman spectra, proves that the pegmatitic phosphates are better studied with Raman spectroscopy.

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This report is a technical assessment of the hydrological environment of the southern Moreton Bay islands and follows the terms of reference supplied by the then Queensland Department of Natural Resources and Water. The terms of reference describe stage 1 as a condition assessment and stage 2 as an assessment of the implications of water planning scenarios on future condition. This report is the first stage of a two-stage investigation whose primary purpose is to identify and assess groundwater dependent ecosystems (GDEs) and the groundwater flow regimes necessary to support them. Within this context, the groundwaters themselves are also considered and comment made on their condition. Information provided in this report will inform an amendment to the Logan Basin Water Resource Plan to incorporate the southern Moreton Bay islands. The study area is the water resource plan amendment area, which includes North and South Stradbroke islands and the smaller islands between these and the mainland, including the inhabited smaller rocky islands—namely, Macleay, Russell, Karragarra, Lamb and Coochiemudlo islands. This assessment is largely a desktop study based on existing information, but incorporates some field observations, input from experts in specific areas and community representatives, and the professional experience and knowledge of the authors. This report reviews existing research and information on the southern Moreton Bay area with an emphasis on North Stradbroke Island, as it represents the largest and most regionally significant groundwater resource in southern Moreton Bay. The report provides an assessment of key waterrelated environmental features, their condition and their degree of dependence on groundwater. This report also assesses the condition and status of ecosystems within this region. In addition, the report identifies information gaps, uncertainties and potential impacts; reviews groundwater models that have been developed for North Stradbroke Island; and makes recommendations on monitoring and research needs.

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This research was done on hureaulite samples from the Cigana claim, a lithium bearing pegmatite with triphylite and spodumene. The mine is located in Conselheiro Pena, east of Minas Gerais. Chemical analysis was carried out by Electron Microprobe analysis and indicated a manganese rich phase with partial substitution of iron. The calculated chemical formula of the studied sample is: (Mn3.23, Fe1.04, Ca0.19, Mg0.13)(PO4)2.7(HPO4)2.6(OH)4.78. The Raman spectrum of hureaulite is dominated by an intense sharp band at 959 cm−1 assigned to PO stretching vibrations of HPO42− units. The Raman band at 989 cm−1 is assigned to the PO43− stretching vibration. Raman bands at 1007, 1024, 1047, and 1083 cm−1 are attributed to both the HOP and PO antisymmetric stretching vibrations of HPO42− and PO43− units. A set of Raman bands at 531, 543, 564 and 582 cm−1 are assigned to the ν4 bending modes of the HPO42− and PO43− units. Raman bands observed at 414, and 455 cm−1 are attributed to the ν2 HPO42− and PO43− units. The intense A series of Raman and infrared bands in the OH stretching region are assigned to water stretching vibrations. Based upon the position of these bands hydrogen bond distances are calculated. Hydrogen bond distances are short indicating very strong hydrogen bonding in the hureaulite structure. A combination of Raman and infrared spectroscopy enabled aspects of the molecular structure of the mineral hureaulite to be understood.

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We have analyzed a frondelite mineral sample from the Cigana mine, located in the municipality of Conselheiro Pena, a well-known pegmatite in Brazil. In the Cigana pegmatite, secondary phosphates, namely eosphorite, fairfieldite, fluorapatite, frondelite, gormanite, hureaulite, lithiophilite, reddingite and vivianite are common minerals in miarolitic cavities and in massive blocks after triphylite. The chemical formula was determined as (Mn0.68, Fe0.32)(Fe3+)3,72(PO4)3.17(OH)4.99. The structure of the mineral was assessed using vibrational spectroscopy. Bands attributed to the stretching and bending modes of PO4 3- and HOPO3 3- units were identified. The observation of multiple bands supports the concept of symmetry reduction of the phosphate anion in the frondelite structure. Sharp Raman and infrared bands at 3581 cm−1 is assigned to the OH stretching vibration. Broad Raman bands at 3063, 3529 and 3365 cm−1 are attributed to water stretching vibrational modes.

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Shale is an increasingly important source of natural gas in the United States. The gas is held in fine pores that need to be accessed by horizontal drilling and hydrofracturing techniques. Understanding the nature of the pores may provide clues to making gas extraction more efficient. We have investigated two Mississippian Barnett Shale samples, combining small-angle neutron scattering (SANS) and ultrasmall-angle neutron scattering (USANS) to determine the pore size distribution of the shale over the size range 10 nm to 10 μm. By adding deuterated methane (CD4) and, separately, deuterated water (D2O) to the shale, we have identified the fraction of pores that are accessible to these compounds over this size range. The total pore size distribution is essentially identical for the two samples. At pore sizes >250 nm, >85% of the pores in both samples are accessible to both CD4 and D2O. However, differences in accessibility to CD4 are observed in the smaller pore sizes (∼25 nm). In one sample, CD4 penetrated the smallest pores as effectively as it did the larger ones. In the other sample, less than 70% of the smallest pores (<25 nm) were accessible to CD4, but they were still largely penetrable by water, suggesting that small-scale heterogeneities in methane accessibility occur in the shale samples even though the total porosity does not differ. An additional study investigating the dependence of scattered intensity with pressure of CD4 allows for an accurate estimation of the pressure at which the scattered intensity is at a minimum. This study provides information about the composition of the material immediately surrounding the pores. Most of the accessible (open) pores in the 25 nm size range can be associated with either mineral matter or high reflectance organic material. However, a complementary scanning electron microscopy investigation shows that most of the pores in these shale samples are contained in the organic components. The neutron scattering results indicate that the pores are not equally proportioned in the different constituents within the shale. There is some indication from the SANS results that the composition of the pore-containing material varies with pore size; the pore size distribution associated with mineral matter is different from that associated with organic phases.

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Automated process discovery techniques aim at extracting models from information system logs in order to shed light into the business processes supported by these systems. Existing techniques in this space are effective when applied to relatively small or regular logs, but otherwise generate large and spaghetti-like models. In previous work, trace clustering has been applied in an attempt to reduce the size and complexity of automatically discovered process models. The idea is to split the log into clusters and to discover one model per cluster. The result is a collection of process models -- each one representing a variant of the business process -- as opposed to an all-encompassing model. Still, models produced in this way may exhibit unacceptably high complexity. In this setting, this paper presents a two-way divide-and-conquer process discovery technique, wherein the discovered process models are split on the one hand by variants and on the other hand hierarchically by means of subprocess extraction. The proposed technique allows users to set a desired bound for the complexity of the produced models. Experiments on real-life logs show that the technique produces collections of models that are up to 64% smaller than those extracted under the same complexity bounds by applying existing trace clustering techniques.

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The robust and diversely useful isoindoline nitroxide, 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl (1; CTMIO), has previously been synthesised in low-to-moderate yields from phthalic anhydride (3). Recent interest in its biological potential as a potent antioxidant and in other areas has seen an increased demand for its production. Herein, three new synthetic routes to CTMIO are presented and their efficiencies assessed. Two routes, via the nitrile 9 and the formyl compound 11, derive from 5-bromo-1,1,3,3-tetramethylisoindoline (6). The third approach starts from the readily accessible starting material, 4-methylphthalic anhydride (12), and proceeds by a methylarene oxidation with potassium permanganate. The three new approaches yield CTMIO in comparable overall yields (16–18 %); however, the synthetic efficiency is most improved when employing the nitrile intermediate 9.

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The aim of this systematic review was to examine the effect of Contrast Water Therapy (CWT) on recovery following exercise induced muscle damage. Controlled trials were identified from computerized literature searching and citation tracking performed up to February 2013. Eighteen trials met the inclusion criteria; all had a high risk of bias. Pooled data from 13 studies showed that CWT resulted in significantly greater improvements in muscle soreness at the five follow-up time points(<6, 24, 48, 72 and 96 hours) in comparison to passive recovery. Pooled data also showed that CWT significantly reduced muscle strength loss at each follow-up time (<6, 24, 48, 72 and 96 hours) in comparison to passive recovery. Despite comparing CWT to a large number of other recovery interventions, including cold water immersion, warm water immersion, compression, active recovery and stretching, there was little evidence for a superior treatment intervention. The current evidence base shows that CWT is superior to using passive recovery or rest after exercise; the magnitudes of these effects may be most relevant to an elite sporting population. There seems to be little difference in recovery outcome between CWT and other popular recovery interventions.

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Microbiology is the science devoted lo the study of organisms that are too small to be seen by the naked eye. These microorganisms are a large and diverse group of free-living forms that exist as single cells or cell clusters. Being free-living, microbial cells are distinct from the cells of animals and plants as the latter are not able to live alone in nature but only in characteristic groups. A single microbial cell, generally, is able to carry out its life processes of growth, respiration and reproduction independently of other cells, either of the same kind or of different kinds. There are five subdisciplines of microbiology: (a) the study of bacteria (bacteriology); (b) the study of viruses (virology); (c) the study of algae (phycology); (d) the study of fungi (mycology); and (e) the study of protozoa (protozoology). In the examination of the environment, all five areas of microbiology are studied. This becomes obvious when discussing the significance of each of these groups of organisms in relation to human health.

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This paper discusses the nature of the conceptual structure in art practice, by example. It draws on insights gained from a practice based research (PBR) approach to making art. The PBR methods used include Reflective Practice and are briefly described. They have informed an understanding of the conceptual structure as an instance of problem framing. This is demonstrated by two creative examples, taken from two interactive artworks. These were informed by an evolving conceptual structure concerned with water.

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Despite the widespread use of paper, plastic or ceramics in dielectric capacitors, water has not been commonly used as a dielectric due to its tendency to become conductive as it easily leaches ions from the environment. We show here that when water is confined between graphene oxide sheets, it can retain its insulating nature and behave as a dielectric. A hydrated graphene oxide film was used as a dielectric spacer to construct a prototype water-dielectric capacitor. The capacitance depends on the water content of the hydrated GO film as well as the voltage applied to the device. Our results show that the capacitance per unit area of the GO film is in the range of 100–800 mF cm �2, which is 5–40 times that of the double layer capacitance per surface area of activated carbon.

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Australia is the driest inhabited continent in the world and persisting droughts have triggered a move toward sensible and sustainable water consumption. Understanding how and where water is consumed in households enables streamlined development of demand management programs and efficient engineering of water infrastructure. End use water consumption analysis is required to gain necessary empirical data of how and where water is consumed. Several end use water consumption studies have been conducted within Australia and around the world with varying results produced. This pilot study paper provides preliminary data from the Gold Coast Watersaver End Use Project which is currently underway. Specifically, the paper includes water end use category volumetric and percentage break downs for 18 single and 32 dual reticulated homes on the Gold Coast (i.e. 50 in total). Moreover, a comparitive analysis between each of the individual households water end use levels is discussed along with other national studies previously completed. The paper finishes with an overview of the greater 200 home end use study conducted on the Gold Coast and its key deliverables and research outcomes.

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Numerous crops grow in sugar regions that have the potential to increase the amount of biomass available to a small bagasse-based pulp factory. Arundo donax and Sorghum offer unique advantages to farmers compared to other agricultural crops. Sorghum bicolour requires only 1/3 of the water of sugarcane. Arundo donax is a very high yield crop, it can also grow with little water but it has the further advantage in that it is also highly stress tolerant, making it suitable for land which is unsuited to other crops. Pulps produced from these crops were benchmarked against sugarcane bagasse pulp. Arundo, sorghum and bagasse were pulped using KOH and anthraquinone to 20 Kappa number so as to produce a bleachable pulp. The unbleached sorghum pulp has better tensile strength properties than the unbleached Arundo pulp (43.8 Nm/g compared to 21.4 Nm/g) and the bleached sorghum pulp tensile strength was similar to bagasse (28.4 Nm/g). At 20 Kappa number, sorghum pulp had acceptable yield for a non-wood fibre (45% c.f. 55% for bagasse), Arundo donax pulp had low tensile strength, and relatively low yield (38.7%), even for an agricultural fibre and required severe cooking conditions to achieve similar delignification to sugarcane bagasse or sorghum. Sorghum and Arundo donax produced thicker handsheets than bagasse (>160 μm c.f. 122 μm for bagasse). In preliminary experiments sorghum and bagasse responded slightly better to Totally Chlorine Free bleaching (QPP), although none achieved a satisfactory brightness level and more optimisation is needed.

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Exposure to cold air, whole body cryotherapy (WBC), is a novel treatment employed by athletes. In WBC individuals dressed in minimal clothing are exposed to a temperature below -100°C for 2-4 min. The use of WBC has been advocated as a treatment for various knee injuries. PURPOSE: To compare the effects of two modalities of cryotherapy, -110°C WBC and 8°C cold water immersion (CWI) on knee skin temperature (Tsk). METHODS: With ethical approval and written informed consent 10 healthy active male participants (26.5±4.9 yr, 183.5±6.0 cm, 90.7±19.9 kg, 26.8±5.0 kg/m2, 23.0±9.3% body fat (measured by DXA), 7.6 ± 2.0 mm patellar skin fold; mean±SD) were exposed to 4 min of CWI and WBC. The treatment order was randomised in a controlled crossover design, with a minimum of 7 days between treatments. During WBC participants stood in a chamber (-60±3°C) for 20 s before entering the main chamber (-110°C±3°C) where they remained for 3 min and 40 s. For CWI participants were seated in a tank filled with cold water (8±0.3°C) and immersed to the level of the sternum for 4 min. Right knee Tsk was assessed via non-contact, infrared thermal imaging. A quadrilateral region of interest was created using inert markers placed 5 cm above and below the most superior and inferior aspect of the patella. Tsk within this quadrilateral was recorded pre, immediately post and every 10 min thereafter for 60 min. Tsk changes were examined using a two-way (treatment x time) repeated measures analyses of variance. In addition, a paired sample t-test was used to compare baseline Tsk before both treatments. RESULTS: Knee Tsk was similar before treatment (WBC: 29.9±0.7°C, CWI: 29.6±0.9°C, p>0.05). There was a significant main effect for treatment (p<0.05) and time (p<0.001). Compared to baseline, Tsk was significantly reduced (p<0.05) immediately post and at 10, 20, 30, 40, 50 and 60 min after both cooling modalities. Knee Tsk was lower (p<0.05) immediately after WBC (19.0±0.9°C) compared to CWI (20.5±0.6°C). However, from 10 to 60 min post, knee Tsk was lower (p<0.05) following the CWI treatment. CONCLUSION: WBC elicited a greater decrease in knee Tsk compared to CWI immediately after treatment. However, both modalities display different recovery patterns and Tsk after CWI was significantly lower than WBC at 10, 20, 30, 40, 50 and 60 min after treatment.

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For more than a hundred years water rights were granted in accordance with the legislation of the states and territories. Until recently, this legislation conferred a relatively unlimited discretion on the relevant regulatory institutions. Over the past 15 years, the Commonwealth has taken a greater interest in how water resources should be managed: first by formulating and funding policies and strategies through COAG, and then by enacting the Water Act 2007. This Act has created a much more prescriptive regime for planning and managing Australia’s water resources while at the same time entrusting its operational implementation to the states and territories. This has the potential to create tensions between the legal regimes of the Commonwealth and those of the states and territories. This article seeks to examine some of these issues.