Nano-droplets deposited in microarrays by femtosecond Ti:sapphire laser-induced forward transfer

The authors present the deposition of nanoscale droplets of Cr using femtosecond Ti:Sapphire Laser-Induced Forward Transfer. Deposits around 300 nm in diameter, significantly smaller than any previously reported, are obtained from a 30 nm thick source film. Deposit size, morphology, and adhesion to a receiver substrate as functions of applied laser fluence are investigated. We show that deposits can be obtained from previously irradiated areas of the source material film with negligible loss of deposition quality, allowing sub-spot size period microarrays to be produced without the need to move the source film

NMR analysis of Nile Blue (C. I. Basic Blue 12) and Thionine (C. I. 52000) in solution

The dyes Nile Blue (C. I. Basic Blue 12, NB) and Thionine (C. I. 52000, TH) were examined in both ionic and neutral forms in different solvents using NMR and UV-visible Spectroscopy to firmly establish the structures of the molecules and to assess the nature and extent of their aggregating characteristics. 1H and 13C NMR assignments and chemical shift data were used along with (for NB) nuclear Overhauser effect information enabling a structure for self-assembly to be proposed. In both cases these data were supplemented with variable temperature, dilution and diffusion-based experimental results using 1H NMR spectroscopy thereby enabling the extended aggregate structures to be assessed in terms of the relative strength of self-association and the extent to which extended aggregates could form. Full and detailed solution phase NMR analysis of such dyes, especially the two studied in this context, have either not been widely reported or have not been studied to the depth presented here. The data and their interpretation form an important addition to the analysis of this class of dye compounds and provide additional insight into the effects of self-assembly on the behaviour of such molecules in various solution-phase environments

Investigations into the reactivity of an anionic gallium (I) N-heterocyclic carbene analogue

This thesis is mainly concerned with investigations into the reactivity of the gallium(I)-heterocyclic carbene (NHC) analogue, K(tmeda) :Ga{ N(Ar)C(H) 2} (Ar = C6H3Pr'2-2,6). Reactions of germanium, tin and lead alkyls, aryls, halides and heterocycles with K(tmeda) :Ga{ N(Ar)C(H) 2} afforded complexes such as K(tmeda) Sn{CH(SiMe3)2}2{Ga{ N(Ar)C(H) 2}}, which exhibits the first structurally characterised Ga Sn bond in a molecular complex. Group 6, 9 and 11 metal halide complexes were treated with K(tmeda) :Ga{ N(Ar)C(H) 2}, yielding complexes such as (IPr)Cu{Ga{ N(Ar)C(H) 2}} and (IPr)Ag{Ga{ N(Ar)C(H) 2}}. These complexes exhibit the first structurally characterised Ga Cu and Ga Ag bonds in molecular complexes. A study of the reactivity of (lPr)Cu{Ga{ N(Ar)C(H) 2}} with unsaturated organic substrates suggested that the Ga Cu bond is quite inert. Salt metathesis reactions of group 10 metal halide complexes with K(tmeda) :Ga{ N(Ar)C(H) 2} afforded complexes such as (dppe)Pt{Ga{ N(Ar)C(H) 2} }2. An investigation into the further reactivity of this complex towards ter/-butylphosphaalkyne yielded a platinum(II) complex, (dppe)Pt{Ga{ N(Ar)C(H) 2}}{Ga{ PC(Bul)C(H)- (NAr)C(H)N(Ar) }}, which exhibits a formally anionic P,N-heterocyclic gallium(I) ligand. The kinetics of the formation of this complex were studied. A novel gallium(III) complex, GaI2{C(But)P(H)C(But)=P} 2, was formed by the disproportionation reaction of :Sn(n4-P2C2But2) with "Gal". The oxidative insertion reaction of K(tmeda) :Ga{ N(Ar)C(H) 2} with FisoH yielded the gallium(III) hydride, {N(Ar)C(H)N(Ar)-K}(H)Ga{ N(Ar)C(H) 2}. Reaction of the digallane(4), Ga{ N(Ar)C(H) 2} 2, with N3-SiMe3 afforded the paramagnetic complex, {u- N(SiMe3)}Ga{ N(Ar)C(H) 2'} 2, which was studied by EPR spectroscopy. A synthetic route to the novel gallium(I) NHC analogue, K(tmeda) :Ga{ N(Ar)C(Me) 2}, is also described. Work performed in Monash University, involving bulky amidinate and guanidinate ligands, is also discussed. A novel cationic boron heterocycle, BrB(Giso) + (Giso" = {N(Ar)}2CNCy2 l, was synthesised from BBr3 and the gallium(I) guanidinate, :Ga(Giso). The use of Sm(Giso)2 as a one-electron reducing agent is exploited in the coupling of two molecules of CS2 by formation of a C S bond to yield {Sm(Giso)2}2(uvr 2:Ti2-SCSCS2). The synthesis of novel rj6-arene rhodium(I) complexes such as (rj4-COD)Rh(r 6-Giso), and their thermal conversion into thermodynamically more stable r 2-chelating forms, are also reported.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Heteroleptic samarium(III) halide complexes probed by fluorescence-detected L3-edge X-ray absorption spectroscopy

Addition of various oxidants to the near-linear Sm(II) complex [Sm(N††)2] (1), where N†† is the bulky bis(triisopropylsilyl)amide ligand {N(SiiPr3)2}, afforded a family of heteroleptic three-coordinate Sm(III) halide complexes, [Sm(N††)2(X)] (X = F, 2-F; Cl, 2-Cl; Br, 2-Br; I, 2-I). In addition, the trinuclear cluster [{Sm(N††)}3(μ2-I)3(μ3-I)2] (3), which formally contains one Sm(II) and two Sm(III) centres, was isolated during the synthesis of 2-I. Complexes 2-X are remarkably stable towards ligand redistribution, which is often a facile process for heteroleptic complexes of smaller monodentate ligands in lanthanide chemistry, including the related bis(trimethylsilyl)amide {N(SiMe3)2} (N′′). Complexes 2-X and 3 have been characterised by single crystal X-ray diffraction, elemental analysis, multinuclear NMR, FTIR and electronic spectroscopy. The Lα1 fluorescence-detected X-ray absorption spectrum recorded at the Sm L3-edge for 2-X exhibited a resolved pre-edge peak defined as an envelope quadrupole-allowed 2p → 4f transition. The X-ray absorption spectral features were successfully reproduced using time-dependent density functional theoretical (TD-DFT) calculations that synergistically supports the experimental observations as well as the theoretical model upon which the electronic structure and bonding in lanthanide complexes is derived

0103-72.6: A New Oxygen-Rich Supernova Remnant in the Small Magellanic Cloud

0103$-$72.6, the second brightest X-ray supernova remnant (SNR) in the Small Magellanic Cloud (SMC), has been observed with the {\it Chandra X-Ray Observatory}. Our {\it Chandra} observation unambiguously resolves the X-ray emission into a nearly complete, remarkably circular shell surrounding bright clumpy emission in the center of the remnant. The observed X-ray spectrum for the central region is evidently dominated by emission from reverse shock-heated metal-rich ejecta. Elemental abundances in this ejecta material are particularly enhanced in oxygen and neon, while less prominent in the heavier elements Si, S, and Fe. We thus propose that 0103$-$72.6 is a new ``oxygen-rich'' SNR, making it only the second member of the class in the SMC. The outer shell is the limb-brightened, soft X-ray emission from the swept-up SMC interstellar medium. The presence of O-rich ejecta and the SNR's location within an H{\small II} region attest to a massive star core-collapse origin for 0103$-$72.6. The elemental abundance ratios derived from the ejecta suggest an $\sim$18 M$_{\odot}$ progenitor star.Comment: 6 pages (ApJ emulator format), including 5 figures and 2 tables. For high quality Figs.1,2, & 3, contact [email protected]. Accepted by the ApJ Letter

Detailed observations of the phytoplankton spring bloom in the stratifying central North Sea

Analysis of detailed time series of bio-optical and temperature data from the North Sea supports the view that a minimum level of turbulence is a prerequisite for the onset and maintenance of the phytoplankton spring bloom in shelf seas, which distinguishes these seas from the open ocean. The start of the spring bloom, primarily diatoms, is controlled by the light regime, while its progress is predominantly dependent upon episodic turbulence input following short periods of stratification, which allow the resuspension of a fast sinking (50-200 m day-1) phytoplankton community from the bottom mixing layer. A relationship between turbulence and the vertical distribution of phytoplankton is proposed which is found at synoptic time scales and on time scales of a day and less. Throughout the spring bloom, algal biomass is either equally distributed through the water column or concentrated in the bottom mixing layer. Growth can only be sustained in the near-surface layer during periods of substantial turbulence input. The establishment of semi-permanent seasonal stratification causes an almost complete reduction in near-surface biomass and a concomitant increase in biomass in the bottom mixing layer which subsequently acts as a source for occasional increased near-surface biomass until early summer

Time Synchronization and Distribution Mechanisms for Space Networks

This work discusses research on the problems of synchronizing and distributing time information between spacecraft based on the Network Time Protocol (NTP), where NTP is a standard time synchronization protocol widely used in the terrestrial network. The Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol was designed and developed for synchronizing spacecraft that are in proximity where proximity is less than 100,000 km distant. A particular application is synchronization between a Mars orbiter and rover. Lunar scenarios as well as outer-planet deep space mother-ship-probe missions may also apply. Spacecraft with more accurate time information functions as a time-server, and the other spacecraft functions as a time-client. PITS can be easily integrated and adaptable to the CCSDS Proximity-1 Space Link Protocol with minor modifications. In particular, PITS can take advantage of the timestamping strategy that underlying link layer functionality provides for accurate time offset calculation. The PITS algorithm achieves time synchronization with eight consecutive space network time packet exchanges between two spacecraft. PITS can detect and avoid possible errors from receiving duplicate and out-of-order packets by comparing with the current state variables and timestamps. Further, PITS is able to detect error events and autonomously recover from unexpected events that can possibly occur during the time synchronization and distribution process. This capability achieves an additional level of protocol protection on top of CRC or Error Correction Codes. PITS is a lightweight and efficient protocol, eliminating the needs for explicit frame sequence number and long buffer storage. The PITS protocol is capable of providing time synchronization and distribution services for a more general domain where multiple entities need to achieve time synchronization using a single point-to-point link

Chronic disease self-management in Aboriginal communities: towards a sustainable program of care in rural communities

Bundoora, VI

The Pothole Hydrology-Linked Systems Simulator (PHyLiSS)—Development and Application of a Systems Model for Prairie-Pothole Wetlands

The North American Prairie Pothole Region covers about 770,000 square kilometers of the United States and Canada (including parts of 5 States and 3 provinces: North Dakota, South Dakota, Montana, Minnesota, Iowa, Saskatchewan, Manitoba, and Alberta). The Laurentide Ice Sheet shaped the landscape of the region about 12,000 to 14,000 years ago. The retreat of the ice sheet left behind low-permeability glacial till and a landscape dotted with millions of depressions known today as prairie potholes. The wetlands that subsequently formed in these depressions, prairie-pothole wetlands, provide critical migratory-bird habitat and support dynamic aquatic communities. Extensive grasslands and productive agricultural systems surround these wetland ecosystems. In prairie-pothole wetlands, the compositions of plant, invertebrate, and vertebrate communities are highly dependent on hydrogeochemical conditions. Regional climate shifts between wet and dry periods affect the length of time that wetlands contain ponded surface water and the chemistry of that ponded water. Land-use change can exacerbate or reduce the effects of climate on wetland hydrology and water chemistry. A mechanistic understanding of the relation among climate, land use, hydrology, chemistry, and biota in prairie-pothole wetlands is needed to better understand the complex, and often interacting, effects of climate and land use on prairie-pothole wetland systems and to facilitate climate and land-use change adaptation efforts. The Pothole Hydrology-Linked Systems Simulator (PHyLiSS) model was developed to address this need. The model simulates water-surface elevation dynamics in prairie-pothole wetlands and quantifies changes in salinity. The PHyLiSS model is unique among other wetland models because it accommodates differing sizes and morphometries of wetland basins, is not dependent on a priori designations of wetland class, and allows for functional changes associated with dynamic shifts in ecohydrological states. The PHyLiSS model also has the capability to simulate wetland salinity, and potential future iterations will also simulate the effects of changing hydrology and geochemical conditions on biota. This report documents the development of the hydrological and geochemical components of the PHyLiSS model and provides example applications

Implementing the Flinders Model of self-management support with Aboriginal people who have diabetes: findings from a pilot study

Programs to increase patients' capacity to manage their chronic disease are growing in popularity with policy makers, health professionals and the general public. However, until this pilot in regional South Australia, Indigenous people rarely participated in such programs. The pilot included extensive consultations with the Indigenous community, ownership of the program by an Aboriginal community-controlled health service, and a key role for Aboriginal and Torres Strait Islander Health Workers as the main coordinators of self-management support. The result was that 60 Aboriginal people participated and achieved notable improvements in health outcomes and personal goals. This pilot demonstrates that mainstream programs are relevant for Aboriginal communities as long as Aboriginal people lead the adaptation process