912 resultados para Calorimetry, indirect


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Hydrotalcites based upon gallium as a replacement for aluminium in hydrotalcite over a Mg/Al ratio of 2:1 to 4:1 were synthesised. The d(003) spacing varied from 7.83 A ° for the 2:1 hydrotalcite to 8.15 A ° for the 3:1 gallium containing hydrotalcite. A comparison is made with the Mg Al hydrotalcite in which the d(003) spacing for the Mg/Al hydrotalcite varied from 7.62 A ° for the 2:1Mg hydrotalcite to 7.98 A ° for the 4:1 hydrotalcite. The thermal stability of the gallium containing hydrotalcite was determined using thermogravimetric analysis. Four mass loss steps at 77, 263–280,485 and 828 degrees C with mass losses of 10.23, 21.55, 5.20 and 7.58% are attributed to dehydration, dehydroxylation and decarbonation. The thermal stability of the galliumcontaining hydrotalcite is slightly less than the aluminium hydrotalcite.

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Objective: Parental illness (PI) may have adverse impacts on youth and family functioning. Research in this area has suffered from the absence of a guiding comprehensive framework. This study tested a conceptual model of the effects of PI on youth and family functioning derived from the Family Ecology Framework (FEF; Pedersen & Revenson, 2005). Method. A total of 85 parents with multiple sclerosis and 127 youth completed questionnaires at Time 1 and 12 months later at Time 2. Results. Structural equation modeling results supported the FEF with regards to physical-illness disability. Specifically, the proposed mediators (role redistribution, stress, and stigma) were implicated in the processes that link parental disability to several domains of youth adjustment. The results suggest that the effects of parental depression (PD) are not mediated through these processes; rather, PD directly affects family functioning, which in turn mediates the effects onto youth adjustment. Family functioning further mediated between PD and youth well-being and behavioral-social difficulties. Conclusions. Although results support the effects of parental-illness disability on youth and family functioning via the proposed mediational mechanisms, the additive effects of PD on youth physical and mental health occur through direct and indirect (via family functioning) pathways, respectively.

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Thermogravimetry combined with evolved gas mass spectrometry has been used to characterise the mineral ardealite and to ascertain the thermal stability of this ‘cave’ mineral. The mineral ardealite Ca2(HPO4)(SO4)•4H2O is formed through the reaction of calcite with bat guano. The mineral shows disorder and the composition varies depending on the origin of the mineral. Thermal analysis shows that the mineral starts to decompose over the temperature range 100 to 150°C with some loss of water. The critical temperature for water loss is around 215°C and above this temperature the mineral structure is altered. It is concluded that the mineral starts to decompose at 125°C, with all waters of hydration being lost after 226°C. Some loss of sulphate occurs over a broad temperature range centred upon 565°C. The final decomposition temperature is 823°C with loss of the sulphate and phosphate anions.

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The need to find an alternative to our current transport situation is widely accepted. In most cities of the world, traffic congestion is commonplace and air pollution is normal. Road fatalities are a regular and almost accepted event. And (in most developed nations) as an indirect consequence of our transport choices, obesity is increasing at an alarming rate. The car is undeniably a major contributor to this situation. Additionally the very structure of our cities has evolved to the point that it can be creditably claimed that the city belongs to the car and not to humans. There are however alternatives. There is a plethora of experimental vehicles in all shapes and configurations. And yet, the car is still king. The question is, how do we pick a winner? What are the aspects of the car that make it so appealing? Are these aspects able to be translated into a more sustainable version? What do we need to incorporate in our designs of new vehicles to make them more appealing to the consumers? In this paper I explore these questions and propose a list of design criteria for more sustainable transport options.

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Objective: To determine the major health related risk factors and provide evidence for policy-making,using health burden analysis on selected factors among general population from Shandong province. Methods: Based on data derived from the Third Death of Cause Sampling Survey in Shandong. Years of life lcrat(YLLs),yearS Iived with disability(YLDs)and disability-adjusted life years(DALYs) were calculated according to the GBD ethodology.Deaths and DALYs attributed to the selected risk factors were than estimated together with the PAF data from GBD 2001 study.The indirect method was employed to estimate the YLDs. Results: 51.09%of the total dearlls and 31.83%of the total DALYs from the Shandong population were resulted from the 19 selected risk factors.High blood pre.ure,smoking,low fruit and vegetable intake,aleohol consumption,indoor smoke from solid fuels,high cholesterol,urban air pollution, physical inactivity,overweight and obesity and unsafe injections in health care settings were identified as the top 10 risk faetors for mortality which together caused 50.21%of the total deaths.Alcohol use,smoking,high blood pressure,Low fruit and vegetable intake, indoor smoke from solid fuels, overweight and obesity,high cholesterol, physical inactivity,urban air pollution and iron-deficiency anemia were proved as the top 10 risk factors related to disease burden and were responsible for 29.04%of the total DALYs. Conclusion: Alcohol use.smoking and high blood pressure were determined as the major risk factors which influencing the health of residents in Shandong. The mortality and burden of disease could be reduced significantly if these major factors were effectively under control.

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High resolution thermogravimetric analysis (TGA) has attracted much attention in the synthesis of organoclays and its applications. In this study, organoclays were synthesised through ion exchange of a single cationic surfactant for sodium ions, and characterised by methods including X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The changes of surface properties in montmorillonite and organoclays intercalated with surfactant were determined using XRD through the changes in the basal spacing. The thermogravimetric analysis (TGA) was applied in this study to investigate more information of the configuration and structural changes in the organoclays with thermal decomposition. There are four different decompositions steps in differential thermogravimetric (DTG) curves. The obtained TG steps are relevant to the arrangement of the surfactant molecules intercalated in montmorillonite and the thermal analysis indicates the thermal stability of surfactant modified clays. This investigation provides new insights into the properties of organoclays and is important in the synthesis and processing of organoclays for environmental applications.

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The removal of the sulfate anion from water using synthetic hydrotalcite (Mg/Al LDH) was investigated using powder x-ray diffraction (XRD) and thermogravimetric analysis (TG). Synthetic hydrotalcite Mg6Al2(OH)16(CO3)∙4H2O was prepared by the co-precipitation method from aluminum and magnesium chloride salts. The synthetic hydrotalcite was thermally activated to a maximum temperature of 380°C. Samples of thermally activated hydrotalcite where then treated with aliquots of 1000ppm sulfate solution. The resulting products where dried and characterized by XRD and TG. Powder XRD revealed that hydrotalcite had been successfully prepared and that the product obtained after treatment with sulfate solution also conformed well to the reference pattern of hydrotalcite. The d(003) spacing of all samples was found to be within the acceptable region for a LDH structure. TG revealed all products underwent a similar decomposition to that of hydrotalcite. It was possible to propose a reasonable mechanism for the thermal decomposition of a sulfate containing Mg/Al LDH. The similarities in the results may indicate that the reformed hydrotalcite may contain carbonate anion as well as sulfate. Further investigation is required to confirm this.

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The mineral newberyite Mg(PO3OH)•3H2O is a mineral that has been found in caves such as the Skipton Lava Tubes (SW of Ballarat, Victoria, Australia), Moorba cave, Jurien Bay, Western Australia, and in the Petrogale Cave (Madura , Eucla, Western Australia). Because these minerals contain water, the minerals lend themselves to thermal analysis. The mineral newberyite is found to decompose at 145°C with a water loss of 31.96%, a result which is very close to the theoretical value. The result shows that the mineral is not stable in caves where the temperature exceeds this value. The implication of this result rests with the removal of kidney stones, which have the same composition as newberyite. Point heating focussing on the kidney stone results in the destruction of the kidney stone.

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Thermogravimetric analysis has been used to determine the thermal stability of the mineral stercorite H(NH4)Na(PO4)·4H2O. The mineral stercorite originated from the Petrogale Cave, Madura, Eucla, Western Australia. This cave is one of many caves in the Nullarbor Plain in the South of Western Australia. The mineral is formed by the reaction of bat guano chemicals on calcite substrates. Upon thermal treatment the mineral shows a strong decomposition at 191°C with loss of water and ammonia. Other mass loss steps are observed at 158, 317 and 477°C. Ion current curves indicate a gain of CO2 at higher temperature and are attributed to the thermal decomposition of calcite impurity.

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Thermogravimetry combined with evolved gas mass spectrometry has been used to characterise the mineral crandallite CaAl3(PO4)2(OH)5•(H2O) and to ascertain the thermal stability of this ‘cave’ mineral. X-ray diffraction proves the presence of the mineral and identifies the products after thermal decomposition. The mineral crandallite is formed through the reaction of calcite with bat guano. Thermal analysis shows that the mineral starts to decompose through dehydration at low temperatures at around 139°C while dehydroxylation occurs over the temperature range 200 to 700°C with loss of OH units. The critical temperature for OH loss is around 416°C and above this temperature the mineral structure is altered. Some minor loss of carbonate impurity occurs at 788°C. This study shows the mineral is unstable above 139°C. This temperature is well above the temperature in caves, which have a maximum temperature of 15°C. A chemical reaction for the synthesis of crandallite is offered and the mechanism for the thermal decomposition is given.

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It is not uncommon for enterprises today to be faced with the demand to integrate and incor- porate many different and possibly heterogeneous systems which are generally independently designed and developed, to allow seamless access. In effect, the integration of these systems results in one large whole system that must be able, at the same time, to maintain the local autonomy and to continue working as an independent entity. This problem has introduced a new distributed architecture called federated systems. The most challenging issue in federated systems is to find answers for the question of how to efficiently cooperate while preserving their autonomous characteristic, especially the security autonomy. This thesis intends to address this issue. The thesis reviews the evolution of the concept of federated systems and discusses the organisational characteristics as well as remaining security issues with the existing approaches. The thesis examines how delegation can be used as means to achieve better security, especially authorisation while maintaining autonomy for the participating member of the federation. A delegation taxonomy is proposed as one of the main contributions. The major contribution of this thesis is to study and design a mechanism to support dele- gation within and between multiple security domains with constraint management capability. A novel delegation framework is proposed including two modules: Delegation Constraint Man- agement module and Policy Management module. The first module is designed to effectively create, track and manage delegation constraints, especially for delegation processes which require re-delegation (indirect delegation). The first module employs two algorithms to trace the root authority of a delegation constraint chain and to prevent the potential conflict when creating a delegation constraint chain if necessary. The first module is designed for conflict prevention not conflict resolution. The second module is designed to support the first module via the policy comparison capability. The major function of this module is to provide the delegation framework the capability to compare policies and constraints (written under the format of a policy). The module is an extension of Lin et al.'s work on policy filtering and policy analysis. Throughout the thesis, some case studies are used as examples to illustrate the discussed concepts. These two modules are designed to capture one of the most important aspects of the delegation process: the relationships between the delegation transactions and the involved constraints, which are not very well addressed by the existing approaches. This contribution is significant because the relationships provide information to keep track and en- force the involved delegation constraints and, therefore, play a vital role in maintaining and enforcing security for transactions across multiple security domains.

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Taxation law can be an incredibly complex subject to absorb, particularly when time is limited. Written specifically for students, Principles of Taxation Law 2011 brings much needed clarity to this area of law. Utilising many methods to make this often daunting subject achievable, particular features of the 2011 edition include: • seven parts: overview and structure, principles of income, deductions and offsets, timing issues, investment and business entities, tax avoidance and administration, and indirect taxes; • clearly structured chapters within those parts grouped under helpful headings; • flowcharts, diagrams and tables, end of chapter practice questions, and case summaries; • an appendix containing all of the up to date and relevant rates; and • the online self-testing component mentor, which provides questions for students of both business and law. Every major aspect of the Australian tax system is covered, with chapters on topics such as goods and services tax, superannuation, offsets, partnerships, capital gains tax, trusts, company tax and tax administration. All chapters have been thoroughly revised. Principles of Taxation Law 2011 is the perfect tool to guide the reader from their initial exposure to the subject to success in taxation law exams. [from publisher's website]

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Taxation law can be an incredibly complex subject to absorb, particularly when time is limited. Written specifically for students, Principles of Taxation Law 2012 brings much needed clarity to this area of law. Utilising many methods to make this often daunting subject achievable, particular features of the 2012 edition include: * seven parts: overview and structure, principles of income, deductions and offsets, timing issues, investment and business entities, tax avoidance and administration, and indirect taxes; * clearly structured chapters within those parts grouped under helpful headings; * flowcharts, diagrams and tables, end of chapter practice questions, and case summaries; * an appendix containing all of the up to date and relevant rates; and * the online self-testing component mentor, which provides questions for students of both business and law. Every major aspect of the Australian tax system is covered, with chapters on topics such as goods and services tax, superannuation, offsets, partnerships, capital gains tax, trusts, company tax and tax administration. All chapters have been thoroughly revised. Principles of Taxation Law 2012 is the perfect tool to guide the reader from their initial exposure to the subject to success in taxation law exams.

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Purpose: We provide an account of the relationships between eye shape, retinal shape and peripheral refraction. Recent findings: We discuss how eye and retinal shapes may be described as conicoids, and we describe an axis and section reference system for determining shapes. Explanations are given of how patterns of retinal expansion during the development of myopia may contribute to changing patterns of peripheral refraction, and how pre-existing retinal shape might contribute to the development of myopia. Direct and indirect techniques for determining eye and retinal shape are described, and results are discussed. There is reasonable consistency in the literature of eye length increasing at a greater rate than height and width as the degree of myopia increases, so that eyes may be described as changing from oblate/spherical shapes to prolate shapes. However, one study indicates that the retina itself, while showing the same trend, remains oblate in shape for most eyes (discounting high myopia). Eye shape and retinal shape are not the same and merely describing an eye shape as being prolate or oblate is insufficient without some understanding of the parameters contributing to this; in myopia a prolate eye shape is likely to involve both a steepening retina near the posterior pole combined with a flattening (or a reduction in steepening compared with an emmetrope) away from the pole.

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Australians are the creators and custodians of a broad range of cultural materials. This material includes literary, photographic, video and audio archives. These archives should be made available to all Australians for access and reuse, as part of a pre-competitive platform which promotes the interests of the Australian public in gaining access to a diverse range of content that contributes to the development of national and cultural identity. This does not mean that all material must be made available for access and reuse for free and in an unrestricted fashion. But for publicly funded content, free and unrestricted access should be the default. The Venturous Australia report on the National Innovation System recommended that “[t]o the maximum extent possible, information, research and content funded by Australian governments – including national collections – should be made freely available over the internet as part of the global public commons.”1 The report further stated that “both for its direct and indirect benefits to Australia and for the greater global good, Australia should energetically and proudly maximise the extent to which it makes government funded content available as part of the global digital commons...