61,481 research outputs found

    Postsynthetic modification of zirconium metal-organic frameworks

    Get PDF
    Metal-organic frameworks (MOFs) have been in the spotlight for a number of years due to their chemical and topological versatility. As MOF research has progressed, highly functionalised materials have become desirable for specific applications, and in many cases the limitations of direct synthesis have been realised. This has resulted in the search for alternative synthetic routes, with postsynthetic modification (PSM), a term used to collectively describe the functionalisation of pre-synthesised MOFs whilst maintaining their desired characteristics, becoming a topic of interest. Advances in the scope of reactions performed are reported regularly; however reactions requiring harsh conditions can result in degradation of the framework. Zirconium-based MOFs present high chemical, thermal and mechanical stabilities, offering wider opportunities for the scope of reaction conditions that can be tolerated, which has seen a number of successful examples reported. This microreview discusses pertinent examples of PSM resulting in enhanced properties for specific applications, alongside fundamental transformations, which are categorised broadly into covalent modifications, surface transformations, metalations, linker and metal exchange, and cluster modifications

    Shall Businesses Profit If Their Owners Lose Their Souls? Examining Whether Closely Held Corporations May Seek Exemptions from the Contraceptive Mandate

    Get PDF
    May for–profit, secular corporations claim the protection of the Religious Freedom Restoration Act (RFRA)? This question is central to numerous lawsuits against the federal government in which business owners argue that certain regulations under the Patient Protection & Affordable Care Act substantially burden the exercise of their religion. This Note examines the threshold hurdle that for–profit business owners must clear to successfully state a claim under RFRA: the question of whether the businesses are “persons” the statute protects. This is an issue of first impression for the U.S. Supreme Court, and it has split the circuit courts of appeal. First, this Note provides an overview of free exercise jurisprudence, with a focus on the ebbs and flows of the Supreme Court’s exemption doctrine. This overview includes a discussion of the Religious Freedom Restoration Act and the laws, regulations, and religious objections that form the basis of the current disputes. Second, this Note introduces the conflict among circuit courts and their varying interpretations of whether for–profit corporations are “persons” under RFRA. Third, this Note assesses this conflict by examining RFRA’s text and the context in which Congress enacted the statute. Nothing within this context precludes corporations from stating RFRA claims. In addition, this Note examines legislative history that supports application of the Dictionary Act, which explains that the word “person” in federal statutes includes corporations. This Note ultimately concludes that RFRA does indeed grant corporations the ability to seek exemptions, but that the statute will require courts to undertake the task of ascertaining the proper contours of the law as applied to different corporate forms

    Digital forensics formats: seeking a digital preservation storage format for web archiving

    Get PDF
    In this paper we discuss archival storage formats from the point of view of digital curation and preservation. Considering established approaches to data management as our jumping off point, we selected seven format attributes which are core to the long term accessibility of digital materials. These we have labeled core preservation attributes. These attributes are then used as evaluation criteria to compare file formats belonging to five common categories: formats for archiving selected content (e.g. tar, WARC), disk image formats that capture data for recovery or installation (partimage, dd raw image), these two types combined with a selected compression algorithm (e.g. tar+gzip), formats that combine packing and compression (e.g. 7-zip), and forensic file formats for data analysis in criminal investigations (e.g. aff, Advanced Forensic File format). We present a general discussion of the file format landscape in terms of the attributes we discuss, and make a direct comparison between the three most promising archival formats: tar, WARC, and aff. We conclude by suggesting the next steps to take the research forward and to validate the observations we have made

    Closing the loop: assisting archival appraisal and information retrieval in one sweep

    Get PDF
    In this article, we examine the similarities between the concept of appraisal, a process that takes place within the archives, and the concept of relevance judgement, a process fundamental to the evaluation of information retrieval systems. More specifically, we revisit selection criteria proposed as result of archival research, and work within the digital curation communities, and, compare them to relevance criteria as discussed within information retrieval's literature based discovery. We illustrate how closely these criteria relate to each other and discuss how understanding the relationships between the these disciplines could form a basis for proposing automated selection for archival processes and initiating multi-objective learning with respect to information retrieval

    The Carbon Challenge for Mixed Enterprise Farms

    Get PDF
    As part of its climate change policy the Australian government has introduced a Mandatory Renewable Energy Target (MRET) scheme and is also attempting to introduce a Carbon Pollution Reduction Scheme (CPRS). Using as a case study a main agricultural region of Australia, this paper examines how farming systems in this region may be affected by the medium term policy settings of these two schemes. A bio-economic model of the region’s farming systems is developed and used to assess the schemes’ impacts on the nature and profitability of the farming systems. Results show a range of profit and enterprise impacts across the range of farming systems. Farms as providers of biomass for electricity generation and small users of electricity are liable to benefit from the MRET scheme, with the extent of benefit depending on the price offered for biomass. By contrast, the CPRS is liable to more profoundly affect farming systems, especially if agriculture is included in the scheme. The impacts of the CPRS on agriculture are mostly conditional on: the amount of free permits allocated to agriculture, the value of trees as carbon sinks, the extent of pass-through of CPRS-related costs onto agriculture and emission permit prices. Dependent on these factors, farm profits can increase by up to 20 percent or decrease by over 30 percent, relative to the ‘no CPRS’ or ‘business-as-usual’ case. If agriculture is covered by the CPRS, and emission permits and tree growth rates are sufficiently high then optimal farm plans typically involve a combination of reduced livestock numbers, the planting of permanent stands of trees on marginal farmland and other changes to the enterprise mix on farms that reduce emissions.agriculture, greenhouse gases, economic modelling, sequestration, Agricultural and Food Policy, Crop Production/Industries, Environmental Economics and Policy, Institutional and Behavioral Economics, International Relations/Trade, Land Economics/Use,

    Successful Supersymmetric Inflation

    Full text link
    We reconsider the problems of cosmological inflation in effective supergravity theories. A singlet field in a hidden sector is demonstrated to yield an acceptable inflationary potential, without fine tuning. In the simplest such model, the requirement of generating the microwave background anisotropy measured by COBE fixes the inflationary scale to be about 101410^{14} GeV, implying a reheat temperature of order 10510^{5} GeV. This is low enough to solve the gravitino problem but high enough to allow baryogenesis after inflation. Such consistency requires that the generation of gravitational waves be negligible and that the spectrum of scalar density perturbations depart significantly from scale-invariance, thus improving the fit to large-scale structure in an universe dominated by cold dark matter. We also consider the problems associated with gravitino production through inflaton decay and with other weakly coupled fields such as the moduli encountered in (compactified) string theories.Comment: 27 pages (LaTeX) including 1 embedded (PostScript) figure. Revised to include a fuller discussion of initial conditions (leading to "eternal" inflation) and the role of moduli; some reordering of sections for greater clarity. Accepted for publication in Nuclear Physics

    Dryland Salinity: Spatial Impacts and Farmers' Options

    Get PDF
    The salinisation of farmland in Australia is a major natural resource management problem. Over the next 20 years a further 1.1 million hectares of broadacre farmland is predicted to become salt-affected. This paper firstly explores the spatial ramifications of the spread of salinity in Australia's agricultural regions. Some of the nation's most profitable grain growing regions will become seriously affected by salinity over the next 20 years. Secondly this paper outlines the nature, uptake and profitability of various salinity management options available to Australian farmers. These options include preventative and containment measures, such as engineering solutions and adoption of deep-rooted perennials, and other options involving adaptation to more saline environments such as commercial use of saline water and salt tolerant fodder plants. Deep-rooted perennial fodder species appear to offer the best short to medium term prospect for managing salinity in most agricultural zones. However, in many situations perennials may not be profitable at the scale required to have a significant impact on the rate of spread of salinity on farmland, or the rate of increase of saltload in rivers and streams.Farm Management,
    • 

    corecore