9,021 research outputs found
Polymer or macrocycle? : cobalt complexes of ditopic 2,2':6',2"-terpyridine ligands with flexible spacers
No full textThe reaction of transition metal ions with ditopic ligands containing two 2,2':6',2"-terpyridine units linked by flexible spacers can give metallosupramolecular polymers, discrete metallomacrocycles or mixtures of the two. The outcome of the coordination depends on the precise reaction conditions as well as the nature of the spacer and the transition metal salt.
This thesis is concerned with the reaction between cobalt(II) salts and bis(2,2':6',2"-terpyridine) ligands in which the metal-binding domains are linked by flexible oligo(ethylene glycol) spacers. An initial study of the ligands and several model mononuclear bis(2,2':6',2"-terpyridine)cobalt(II) and (III) complexes gave some insight into the solid state and solution properties of these systems, and PGSE NMR spectroscopy was found to be a useful tool for determination of the size of both the ligands and the cobalt(III) complexes in solution. The reaction of the ditopic ligands with cobalt(II) acetate tetrahydrate in pure alcohol was found to cause the decomposition of the ligand and the formation of a mononuclear bis(4'-alkoxy-2,2':6',2"-terpyridine)cobalt(II) complex. This reaction was extended to monotopic 4'-substituted-2,2':6',2"-terpyridines and can be considered as a reaction giving rise to polymer end-capping units, thus influencing the final outcome of the coordination. The effect of the anion on the coordination was considered further, and the speciation of mono- and bis(2,2':6',2"-terpyridine)cobalt(II) complexes in solution was investigated using the 4'-methoxy-2,2':6',2"-terpyridine ligand. The product mixtures were found to depend heavily on the anion, solvent and initial ratio of ligand to metal salt. Similar behaviour was observed for a model ditopic ligand. The presence of the mono(2,2':6',2"-terpyridine)cobalt(II) complexes within a system containing the ditopic ligands would also provide polymer end-capping units, influencing the speciation of these mixtures. Finally, a detailed study of the product mixtures obtained from the reactions of the ditopic ligands with cobalt(II) salts revealed a complex dependence of the speciation of many bis(2,2':6',2"-terpyridine)cobalt(II) complexes on the ligand, anion, solvent, concentration and other seemingly minor reaction parameters. Using the PGSE NMR spectroscopic technique, the sizes of some of the metallomacrocyclic species present in the equilibrium mixtures could be determined. These measurements were in excellent agreement with X-ray crystallographic data. Analysis of initial product mixtures using the same technique suggested that the initial kinetic products of the complexation are significantly larger species
Characterization of optimized Na+ and Cl? liquid membranes for use with extracellular, self-referencing microelectrodes
No full textSelf-referencing with ion-selective microelectrodes (ISMs) is a useful approach for monitoring near-real-time ion flux near single cells and across epithelia. While ISMs for H+, Ca2+, and K+ have been optimized for use with self-referencing, ISMs for two other primary inorganic ions, Na+ and Cl-, have not. In this study, we have characterized ISMs based on three Na+ ionophores (I, VI, and X) and one Cl- ionophore to assess their suitability for use with self-referencing. ISMs constructed with Na+ ionophore VI have short response times (approximately 100 ms) but possess nearly an order of magnitude less selectivity for Na+ over K+ than ISMs constructed with Na+ ionophore X. The Na+ ionophore X mixture was enhanced to give it a shorter response time while not compromising its selectivity. A Cl(-)-selective microelectrode was constructed and characterized with superior anionic selectivity compared with previously reported Cl- ISMs used with self-referencing. This Cl(-)-selective microelectrode, however, has a relatively slow response time (approximately 3 s), thus requiring changes to the self-referencing protocol. Self-referencing with these ISMs will enable near-real-time ion flux measurements for Na+ and Cl-
The impact and effectiveness of equity focused health impact assessment in health service planning
No full textThis ebook looks at the use of equity focused health impact assessment (EFHIA) on health service plans. It examines:
What are the direct and indirect impacts of EFHIAs conducted on health sector plans?
Does EFHIA improve the consideration of equity in the development and implementation of health sector plans?
How does EFHIA improve the consideration of equity in health planning?
This ebook describes the use and evolution of health impact assessment (HIA) and EFHIA internationally and in Australia, how it has been used in relation to health service plans, examines its effectiveness and impacts on decision-making and implementation and examines several EFHIAs using case study and interpretive description methodologies.
This research shows that EFHIA has the potential to have both direct and indirect impacts on health service planning. These impacts are influenced by a broad range of factors however. The case studies in this ebook show that engagement with the EFHIA process and the extent to which EFHIA is regarded as a broader learning process are important factors that mediate the extent to which EFHIAs influence subsequent activities.
This research suggests that it is not possible to adequately describe the full range of impacts of EFHIA on decision-making and implementation without looking at perceptions about EFHIA’s effectiveness, in particular the perceptions of those involved in the EFHIA and those responsible for acting on its recommendations. These perceptions change over time, suggesting that future research on the effectiveness of HIA should look at the mechanisms by which this change occurs.
The ebook makes two theoretical contributions in the form of (i) a typology for HIAs and (ii) a conceptual framework for evaluating the impact and effectiveness of HIAs. This conceptual framework is tested for its applicability and refined.
The ebook and the accompanying publications were written to fulfil the requirements for a Doctor of Philosophy in Public Health at the University of New South Wales
Open access self-archiving: An author study
No full textThis, our second author international, cross-disciplinary study on open access had 1296 respondents. Its focus was on self-archiving. Almost half (49%) of the respondent population have self-archived at least one article during the last three years. Use of institutional repositories for this purpose has doubled and usage has increased by almost 60% for subject-based repositories. Self-archiving activity is greatest amongst those who publish the largest number of papers. There is still a substantial proportion of authors unaware of the possibility of providing open access to their work by self-archiving. Of the authors who have not yet self-archived any articles, 71% remain unaware of the option. With 49% of the author population having self-archived in some way, this means that 36% of the total author population (71% of the remaining 51%), has not yet been appraised of this way of providing open access. Authors have frequently expressed reluctance to self-archive because of the perceived time required and possible technical difficulties in carrying out this activity, yet findings here show that only 20% of authors found some degree of difficulty with the first act of depositing an article in a repository, and that this dropped to 9% for subsequent deposits. Another author worry is about infringing agreed copyright agreements with publishers, yet only 10% of authors currently know of the SHERPA/RoMEO list of publisher permissions policies with respect to self-archiving, where clear guidance as to what a publisher permits is provided. Where it is not known if permission is required, however, authors are not seeking it and are self-archiving without it. Communicating their results to peers remains the primary reason for scholars publishing their work; in other words,
researchers publish to have an impact on their field. The vast majority of authors (81%) would willingly comply with a mandate from their employer or research funder to deposit copies of their articles in an institutional or subject-based repository. A further 13% would comply reluctantly; 5% would not comply with such a mandate
Progress of international hydrogen production network for the thermochemical Cu–Cl cycle
No full textThis paper presents recent advances by an international team which is developing the thermochemical copper–chlorine (Cu–Cl) cycle for hydrogen production. Development of the Cu–Cl cycle has been pursued by several countries within the framework of the Generation IV International Forum (GIF) for hydrogen production with the next generation of nuclear reactors. Due to its lower temperature requirements in comparison with other thermochemical cycles, the Cu–Cl cycle is particularly well matched with Canada's Generation IV reactor, SCWR (Super-Critical Water Reactor), as well as other heat sources such as solar energy or industrial waste heat. In this paper, recent developments of the Cu–Cl cycle are presented, specifically involving unit operation experiments, corrosion resistant materials and system integration.Atomic Energy of Canada LimitedOntario Research Excellence FundNatural Sciences and Engineering Research Council of CanadaUniversity Network of Excellence in Nuclear Engineering (UNENE)Canada Research Chairs progra
ŻYCIE UKRYTE W SŁOWIE. "BEKSIŃSCY. PORTRET PODWÓJNY" MAGDALENY GRZEBIAŁKOWSKIEJ W ŚWIETLE POSTSTRUKTURALIZMU
No full textLife Hidden in Words. Magdalena Grzebiałkowska\u27s "Beksińscy. Portret podwójny" and Poststructuralism
The article analyzes Magdalena Grzebiałkowska\u27s biographical "Beksińscy. Portret podwójny" which focuses on the lives of Zdzisław Beksiński and Tomasz Beksiński. The author looks at the construction of the biography and its relationship to poststructuralism, which allows for an appreciation of the literary features of the book. He points to how the specificity of the content, language, a mode of narration in Grzebiałkowska\u27s book make it a full-fledged literary work itself. As such the book departs from a typical biographical scheme. Juxtaposing the book with poststructural ideas leads to the reconsideration of the role of the author in the process of shaping of a biographical narrative
Sodium chloride transport of normal and dietary enlarged rat cecum in vitro
No full textSodium chloride transport across isolated cecum mucosa was investigated in normal rats and rats with adaptive cecum growth induced by dietary polyethylene glycol (PEG). The normal cecum absorbed CI in excess of Na with a small short-circuit current (Isc). Dietary adaptation led to large equivalent increments of Na and Cl net absorption without adequate Ise change. Inhibitor studies (mucosal amiloride 10(-3) and 10(-4) M; mucosal 4,4-diisolhiocyanatostilbene-2,2-disulfonic acid 5 x 10(-5) M;serosal furosemide 10(-3) M;serosal ouabain 10(-3) M) suggested that normal cecal NaCl absorption involves electroneutral Na/N and Cl/HCO3 exchange at the apical and Na-K-ATPase-mediated exit across the basolateral cell membrane. Dietary adaptation stimulates the loosely coupled antiports and possibly activates a small serosally located NaCl cotransport. Comparative histology showed flattening of all tissue layers and widening of crypts in PEG animals. Crypt widening may facilitate ion access to underutilized transport sites and, at least in part, explain the increased absorption of the enlarged cecum
Systems, methods and devices for the capture and hydrogenation of carbon dioxide with thermochemical Cu—Cl and Mg—Cl—Na/K—CO2 cycles
No full textSystems, methods, and devices for producing hydrogen and capturing CO2 from emissions combine both H2 production and CO2 capture processes in forms of thermochemical cycles to produce useful products from captured CO2. The thermochemical cycles are copper-chlorine (Cu—Cl) and magnesium-chlorine-sodium/potassium cycles (Mg—Cl—Na/K—CO2). One system comprises a Cu—Cl cycle, a CO2 capture loop, and a hydrogenation cycle. Another system comprises an Mg—Cl—Na/K—CO2 cycle and a hydrogenation cycle. Devices for hydrogen production, CO2 capture, hydrogenation, and process and equipment integration include a two-stage fluidized/packed bed, hybrid two-stage spray-fluidized/packed bed reactor, a two-stage wet-mode absorber, a hybrid two-stage absorber, and a catalyst packed/fluidized bed reactor
Clean hydrogen production with the Cu–Cl cycle – Progress of international consortium, I: Experimental unit operations
No full textAdvancement of the thermochemical copper–chlorine (Cu–Cl) cycle for hydrogen production is reviewed and discussed in this paper. Individual unit operations and their linkage into an integrated cycle are being developed by a Canadian consortium, as part of the Generation IV International Forum (GIF) for hydrogen production with the next generation of nuclear reactors. This paper focuses on the consortium’s latest advances on the Cu–Cl cycle, particularly with respect to hydrogen production with Canada’s Generation IV reactor, called SCWR (Super-Critical Water Reactor). Other heat sources may also be utilized for the Cu–Cl cycle, such as solar energy or industrial waste heat. In this first of two companion papers, recent developments in Canada’s nuclear hydrogen program are reported, specifically unit operation experiments of the Cu–Cl cycle and system integration. The following second companion paper will present system modeling with Aspen Plus, corrosion resistant materials, thermochemistry, safety, and reliability aspects of the Cu–Cl cycle.Atomic Energy of Canada LimitedOntario Research Excellence FundNatural Sciences and Engineering Research Council of CanadaUniversity Network of Excellence in Nuclear Engineering (UNENE)Canada Research Chairs progra
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