110 resultados para 263


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A novel composite material based on deposition of nanosized zero-valent iron (nZVI) particles on acid-leached diatomite was synthesised for the removal of a chlorinated contaminant in water. The nZVI /diatomite composites were characterized by X-ray diffraction, scanning electron microscopy, elemental analysis, transmission electron microscopy and X-ray photoelectron spectroscopy. Compared with the pure nZVI particles, better dispersion of nZVI particles on the surface or inside the pores of diatom shells was observed. The herbicide simazine was selected as the model chlorinated contaminant and the removal efficiency by nZVI /diatomite composite was compared with that of the pristine nZVI and commercial iron powder. It was found that the diatomite supported nZVI composite material prepared by centrifugation exhibits relatively better efficient activity in decomposition of simazine than commercial Fe, lab synthesized nZVI and composite material prepared via rotary evaporation, and the optimum experimental conditions were obtained based on a series of batch experiments. This study on immobilizing nZVI particles onto diatomite opens a new avenue for the practical application of nZVI and the diatomite-supported nanosized zero-valent iron composite materials have potential applications in environmental remediation.

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Twitter and other social media have become increasingly important tools for maintaining the relationships between fans and their idols across a range of activities, from politics and the arts to celebrity and sports culture. Twitter, Inc. itself has initiated several strategic approaches, especially to entertainment and sporting organisations; late in 2012, for example, a Twitter, Inc. delegation toured Australia in order to develop formal relationships with a number of key sporting bodies covering popular sports such as Australian Rules Football, A-League football (soccer), and V8 touring car racing, as well as to strengthen its connections with key Australian broadcasters and news organisations (Jackson & Christensen, 2012). Similarly, there has been a concerted effort between Twitter Germany and the German Bundesliga clubs and football association to coordinate the presence of German football on Twitter ahead of the 2012–2013 season: the Twitter accounts of almost all first-division teams now bear the official Twitter verification mark, and a system of ‘official’ hashtags for tweeting about individual games (combining the abbreviations of the two teams, e.g. #H96FCB) has also been instituted (Twitter auf Deutsch, 2012).

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Where a secured lender elects to appoint a receiver and manager, the appointment document standardly provides for the receiver and manager to act as the agent of the debtor. This article considers the significance of this agency in the context of three specific issues that have the potential to arise in the receivership of a corporate borrower across all Australian jurisdictions.

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As all-atom molecular dynamics method is limited by its enormous computational cost, various coarse-grained strategies have been developed to extend the length scale of soft matters in the modeling of mechanical behaviors. However, the classical thermostat algorithm in highly coarse-grained molecular dynamics method would underestimate the thermodynamic behaviors of soft matters (e.g. microfilaments in cells), which can weaken the ability of materials to overcome local energy traps in granular modeling. Based on all-atom molecular dynamics modeling of microfilament fragments (G-actin clusters), a new stochastic thermostat algorithm is developed to retain the representation of thermodynamic properties of microfilaments at extra coarse-grained level. The accuracy of this stochastic thermostat algorithm is validated by all-atom MD simulation. This new stochastic thermostat algorithm provides an efficient way to investigate the thermomechanical properties of large-scale soft matters.

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During the Senate Inquiry into 'milk price wars' in 2011, Senator Nick Xenophon accused the Australian Competition and Consumer Commission (ACCC) of being 'less effective than a toothless Chihuahua'. This follows the ACCC's lack of action regarding the reported abuse of market power of Australia's supermarket duopoly, where an extensive inquiry into the competitiveness of retail prices in 2008 found grocery retailing to be 'workably competitive' despite numerous claims to the contrary. How can farmers' submissions to the inquiry that cite market abuse be reconciled with the ACCC's finding that all is well in the food supply chain? Following an in-depth examination of 53 farmer submissions to the inquiry, we conclude that the findings of the ACCC are commensurate with the neoliberal economisation of the political sphere, where commercial entities 'legitimately' govern beyond their corporate boundaries, often using disciplinary measures that were once exclusive to governments. We argue that such clear structural inequalities between farmers and major corporations is reason to re-regulate markets and reinsert a stronger role for government to 'level the playing field'.

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Rakaposhi is a synchronous stream cipher, which uses three main components: a non-linear feedback shift register (NLFSR), a dynamic linear feedback shift register (DLFSR) and a non-linear filtering function (NLF). NLFSR consists of 128 bits and is initialised by the secret key K. DLFSR holds 192 bits and is initialised by an initial vector (IV). NLF takes 8-bit inputs and returns a single output bit. The work identifies weaknesses and properties of the cipher. The main observation is that the initialisation procedure has the so-called sliding property. The property can be used to launch distinguishing and key recovery attacks. The distinguisher needs four observations of the related (K,IV) pairs. The key recovery algorithm allows to discover the secret key K after observing 29 pairs of (K,IV). Based on the proposed related-key attack, the number of related (K,IV) pairs is 2(128 + 192)/4 pairs. Further the cipher is studied when the registers enter short cycles. When NLFSR is set to all ones, then the cipher degenerates to a linear feedback shift register with a non-linear filter. Consequently, the initial state (and Secret Key and IV) can be recovered with complexity 263.87. If DLFSR is set to all zeros, then NLF reduces to a low non-linearity filter function. As the result, the cipher is insecure allowing the adversary to distinguish it from a random cipher after 217 observations of keystream bits. There is also the key recovery algorithm that allows to find the secret key with complexity 2 54.

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Management of the industrial nations' hazardous waste is a current and exponentially increasing, global threatening situation. Improved environmental information must be obtained and managed concerning the current status, temporal dynamics and potential future status of these critical sites. To test the application of spatial environmental techniques to the problem of hazardous waste sites, as Superfund (CERCLA) test site was chosen in an industrial/urban valley experiencing severe TCE, PCE, and CTC ground water contamination. A paradigm is presented for investigating spatial/environmental tools available for the mapping, monitoring and modelling of the environment and its toxic contaminated plumes. This model incorporates a range of technical issues concerning the collection of data as augmented by remotely sensed tools, the format and storage of data utilizing geographic information systems, and the analysis and modelling of environment through the use of advance GIS analysis algorithms and geophysic models of hydrologic transport including statistical surface generation. This spatial based approach is evaluated against the current government/industry standards of operations. Advantages and lessons learned of the spatial approach are discussed.

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In this Account we have compiled a list of reliable bond energies that are based on a set of critically evaluated experiments. A brief description of the three most important experimental techniques for measuring bond energies is provided. We demonstrate how these experimental data can be applied to yield the heats of formation of organic radicals and the bond enthalpies of more than 100 representative organic molecules.

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Property in an elusive concept. In many respects it has been regarded as a source of authority to use, develop and make decisions about whatever is the subject matter of this right of ownership. This is true whether the holder of this right of ownership is a private entity or a public entity. Increasingly a right of ownership of this kind has been recognised not only as a source of authority but also as a mechanism for restricting or limiting and perhaps even prohibiting existing or proposed activities that impact upon the environment. It is increasingly therefore an instrument of control as much as an instrument of authorisation. The protection and conservation of the environment are ultimately a matter of the public interest. This is not to suggest that the individual holders of rights of ownership are not interested in protecting the environment. It is open to them to do so in the exercise of a right of ownership as a source of authorisation. However a right of ownership – whether private or public – has become increasingly the instrument according to which the environment is protected and conserved. This article addresses these issues from a doctrinal as well as a practical perspective about how the environment is managed. It does so in five ways: ●considering briefly property as a concept ●reviewing property in its historical context ●analysing property as a human right ●examining property in natural resources ●reviewing judicial approaches to property in natural resources.

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A growing interest is seen for designing intelligent environments that support personally meaningful, sociable and rich everyday experiences. In this paper we describe an intelligent, large screen display called Panorama that is aimed at supporting and enhancing social awareness within an academic work environment. Panorama is not intended to provide instrumental or other productivity related information. Rather, the goal of Panorama is to enhance social awareness by providing interpersonal and rich information related to co-workers and their everyday interactions in the department. A two-phase assessment of Panorama showed to promote curiosity and interest in exploring different activities in the environment.

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In this work, 17-polychlorinated dibenzo-pdioxin/furan (PCDD/Fs) isomers were measured in ambient air at four urban sites in Seoul, Korea (from February to June 2009). The concentrations of their summed values RPCDD/Fs) across all four sites ranged from 1,947 (271 WHO05 TEQ) (Jong Ro) to 2,600 (349 WHO05 TEQ) fg/m3 (Yang Jae) with a mean of 2,125 ± 317) fg/m3 (292 WHO05 TEQ fg/m3). The sum values for the two isomer groups of RPCDD and RPCDF were 527 (30 WHO05 TEQ) and 1,598 (263 WHO05 TEQ) fg/m3, respectively. The concentration profile of individual species was dominated by the 2,3,4,7,8-PeCDF isomer, which contributed approximately 36 % of the RPCDD/Fs value. The observed temporal trends in PCDD/F concentrations were characterized by relative enhancement in the winter and spring. The relative contribution of different sources, when assessed by principal component analysis, is explained by the dominance of vehicular emissions along with coal (or gas) burning as the key source of ambient PCDD/Fs in the residential areas studied.

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Background Understanding the factors that influence physical activity behavior is important in the design of intervention programs targeted at youth. Methods A prospective study design was used to identify the predictors of vigorous physical activity (VPA) (greater than or equal to 6 METs) and moderate and vigorous physical activity (MVPA) (greater than or equal to 3 METs) among 202 rural, predominantly African-American children. Selected social-cognitive determinants of physical activity were assessed via questionnaire in the fifth grade. Participation in VPA and MVPA was assessed via the previous day physical activity recall 1 year later in the sixth grade. Results For girls, participation in community sports, self-efficacy in overcoming barriers, enjoyment of school physical education, race (white > black), and perception of mother's activity level (active vs inactive) were significant predictors of VPA. For MVPA, participation in community sports and self-efficacy in overcoming barriers were significant predictors. For boys, self-efficacy in overcoming barriers was the only significant predictor of VPA, while beliefs regarding activity outcomes and participation in community sports were significant predictors of MVPA. Conclusion Social-cognitive constructs such as physical activity self-efficacy, access to community physical activity outlets, and positive beliefs regarding physical activity outcomes are important predictors of future physical activity behavior among rural, predominantly African-American children.

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We model the hazard rate for car ownership spells. Our model allows us to distinguish among different types of adverse selection effects by observing the type of unobserved heterogeneity across owners of the same car. Our empirical results strongly suggest that there is a lemons effect because there is significant unobserved heterogeneity. However, they also suggest that the lemons effect is caused by the first owner rather than the manufacturer. Had the manufacturer created the lemon, the unobserved heterogeneity would be positively correlated over all owners of a given car. Instead we observe a negative correlation between the unobserved heterogeneity term for the first owner and the unobserved heterogeneity term for subsequent owners. © 2008 Elsevier B.V. All rights reserved.

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We observe that MDS codes have interesting properties that can be used to construct ideal threshold schemes. These schemes permit the combiner to detect cheating, identify cheaters and recover the correct secret. The construction is later generalised so the resulting secret sharing is resistant against the Tompa-Woll cheating.