Quantitative silicoflagellate data from the southern Indic Ocean from ODP Holes 188-1165B, 120-748B and 120-751A

In the modern marine environment the silicoflagellate genus Dictyocha is rare, or absent, south of the Antarctic polar front (APF); the genus Distephanus, in contrast, is dominant. In sediments recovered from ODP Site 1165, 1600 km south of the front, however, three intervals where Dictyocha is abundant are interpreted to represent Pliocene warm events. Comparison of our data with Ciesielski and Weaver's [1974] modern core top silicoflagellate relationship with sea surface temperature (SST) indicates that at Site 1165 mean annual SST was approximately 5°C at 3.7 Ma (event I), and approximately 4°C at 4.3-4.4 Ma (event II) and 4.55-4.8 Ma (event III). Event I represents a 5.5°C warming, and events II and III represents a 4.5°C warming relative to modern mean annual SST. Dictyocha is absent from other Site 1165 Pliocene intervals, which suggests that cooler SST (<2°C) prevailed. The warm events detected at Site 1165 may represent times when North Atlantic Deep Water production and ocean heat transport into the Southern Ocean exerted maximum influence.

GIS-Based Suitability Analysis and Planning of Green Infrastructure: A Case of the PPCOD, Capitol Hill

Thesis (Master's)--University of Washington, 2016-06

Mixing Regimes in the Amundsen Basin of the Arctic Ocean

Thesis (Ph.D.)--University of Washington, 2016-06

Structure and thermal stability of Langmuir-Blodgett films of barium arachidate

The structures of multilayer Langmuir-Blodgett films of barium arachidate before and after heat treatment have been investigated using both atomic force microscopy (AFM) and grazing incidence synchrotron X-ray diffraction (GIXD). AFM gave information on surface morphology at molecular resolution while GIXD provided quantitative details of the lattice structures of the films with their crystal symmetries and lattice constants. As-prepared films contained three coexisting structures: two triclinic structures with the molecularchains tilted by about 20degrees from the film normal and with 3 x 1 or 2 x 2 super-lattice features arising from height modulation of the molecules in the films; a rectangular structure with molecules perpendicular to the film surface. Of these, the 3 x 1 structure is dominant with a loose correlation between the bilayers. In the film plane both superstructures are commensurate with the local structures, having different oblique symmetries. The lattice constants for the 3 x 1 structure are a(s) = 3a = 13.86 Angstrom, b(s) = b = 4.31 Angstrom and gamma(s) = gamma = 82.7degrees; for the 2 x 2 structure a(s) = 2a = 16.54 Angstrom, b(s) = 2b = 9.67 Angstrom, gamma(s) = gamma = 88degrees. For the rectangular structure the lattice constants are a = 7.39 Angstrom, b = 4.96 Angstrom and gamma = 90degrees. After annealing, the 2 x 2 and rectangular structures were not observed, while the 3 x 1 structure had developed over the entire film. For the annealed films the correlation length in the film plane is about twice that in the unheated films, and in the out-of-plane direction covers two bilayers. The above lattice parameters, determined by GIXD, differed significantly from the values obtained by AFM, due possibly to distortion of the films by the scanning action of the AFM tip. (C) 2004 Published by Elsevier B.V.

Modeling of adsorption on nongraphitized carbon surface: GCMC simulation studies and comparison with experimental data

We model nongraphitized carbon black surfaces and investigate adsorption of argon on these surfaces by using the grand canonical Monte Carlo simulation. In this model, the nongraphitized surface is modeled as a stack of graphene layers with some carbon atoms of the top graphene layer being randomly removed. The percentage of the surface carbon atoms being removed and the effective size of the defect ( created by the removal) are the key parameters to characterize the nongraphitized surface. The patterns of adsorption isotherm and isosteric heat are particularly studied, as a function of these surface parameters as well as pressure and temperature. It is shown that the adsorption isotherm shows a steplike behavior on a perfect graphite surface and becomes smoother on nongraphitized surfaces. Regarding the isosteric heat versus loading, we observe for the case of graphitized thermal carbon black the increase of heat in the submonolayer coverage and then a sharp decline in the heat when the second layer is starting to form, beyond which it increases slightly. On the other hand, the isosteric heat versus loading for a highly nongraphitized surface shows a general decline with respect to loading, which is due to the energetic heterogeneity of the surface. It is only when the fluid-fluid interaction is greater than the surface energetic factor that we see a minimum-maximum in the isosteric heat versus loading. These simulation results of isosteric heat agree well with the experimental results of graphitization of Spheron 6 (Polley, M. H.; Schaeffer, W. D.; Smith, W. R. J. Phys. Chem. 1953, 57, 469; Beebe, R. A.; Young, D. M. J. Phys. Chem. 1954, 58, 93). Adsorption isotherms and isosteric heat in pores whose walls have defects are also studied from the simulation, and the pattern of isotherm and isosteric heat could be used to identify the fingerprint of the surface.

Valence-tautomeric RbMnFe Prussian blue analogues:composition and time stability investigation

Three different stoichiometric forms of RbMn[Fe(CN) ]y·zHO [x = 0.96, y = 0.98, z = 0.75 (1); x = 0.94, y = 0.88, z = 2.17 (2); x = 0.61, y = 0.86, z = 2.71 (3)] Prussian blue analogues were synthesized and investigated by magnetic, calorimetric, Raman spectroscopic, X-ray diffraction, and Fe Mössbauer spectroscopic methods. Compounds 1 and 2 show a hysteresis loop between the high-temperature (HT) Fe(S = 1/2)-CN-Mn(S = 5/2) and the low-temperature (LT) Fe(S = 0)-CN-Mn(S = 2) forms of 61 and 135 K width centered at 273 and 215 K, respectively, whereas the third compound remains in the HT phase down to 5 K. The splitting of the quadrupolar doublets in the Fe Mössbauer spectra reveal the electron-transfer-active centers. Refinement of the X-ray powder diffraction profiles shows that electron-transfer-active materials have the majority of the Rb ions on only one of the two possible interstitial sites, whereas nonelectron-transfer-active materials have the Rb ions equally distributed. Moreover, the stability of the compounds with time and following heat treatment is also discussed. © Wiley-VCH Verlag GmbH & Co. KGaA, 2009.

Modelling of transient heat transfer in annealing furnaces

This is a study of heat transfer in a lift-off furnace which is employed in the batch annealing of a stack of coils of steel strip. The objective of the project is to investigate the various factors which govern the furnace design and the heat transfer resistances, so as to reduce the time of the annealing cycle, and hence minimize the operating costs. The work involved mathematical modelling of patterns of gas flow and modes of heat transfer. These models are: Heat conduction and its conjectures in the steel coils;Convective heat transfer in the plates separating the coils in the stack and in other parts of the furnace; and Radiative and convective heat transfer in the furnace by using the long furnace model. An important part of the project is the development of numerical methods and computations to solve the transient models. A limited number of temperature measurements was available from experiments on a test coil in an industrial furnace. The mathematical model agreed well with these data. The model has been used to show the following characteristics of annealing furnaces, and to suggest further developments which would lead to significant savings: - The location of the limiting temperature in a coil is nearer to the hollow core than to the outer periphery. - Thermal expansion of the steel tends to open the coils, reduces their thermal conductivity in the radial direction, and hence prolongs the annealing cycle. Increasing the tension in the coils and/or heating from the core would overcome this heat transfer resistance. - The shape and dimensions of the convective channels in the plates have significant effect on heat convection in the stack. An optimal design of a channel is shown to be of a width-to-height ratio equal to 9. - Increasing the cooling rate, by using a fluidized bed instead of the normal shell and tube exchanger, would shorten the cooling time by about 15%, but increase the temperature differential in the stack. - For a specific charge weight, a stack of different-sized coils will have a shorter annealing cycle than one of equally-sized coils, provided that production constraints allow the stacking order to be optimal. - Recycle of hot flue gases to the firing zone of the furnace would produce a. decrease in the thermal efficiency up to 30% but decreases the heating time by about 26%.

Local shell-side coefficients in shell and tube exchanges the use of a mass transfer technique

A diffusion-controlled electrochemical mass transfer technique has been employed in making local measurements of shell-side coefficients in segmentally baffled shell and tube heat exchangers. Corresponding heat transfer data are predicted through the Chilton and Colburn heat and mass transfer analogy. Mass transfer coefficients were measured for baffle spacing lengths of individual tubes in an internal baffle compartment. Shell-side pressure measurements were also made. Baffle compartment average coefficients derived from individual tube coefficients are shown to be in good agreement with reported experimental bundle average heat transfer data for a heat exchanger model of similar geometry. Mass transfer coefficients of individual tubes compare favourably with those obtained previously by another mass transfer technique. Experimental data are reported for a variety of segmental baffle configurations over the shell-side Reynolds number range 100 to 42 000. Baffles with zero clearances were studied at three baffle cuts and two baffle spacings. Baffle geometry is shown to have a large effect on the distribution of tube coefficients within the baffle compartment. Fluid "jetting" is identified with some baffle configurations. No simple characteristic velocity is found to correlate zonal or baffle compartment average mass transfer data for the effect of both baffle cut and baffle spacing. Experiments with baffle clearances typical of commercial heat exchangers are also reported. The effect of leakage streams associated with these baffles is identified. Investigations were extended to double segmental baffles for which no data had previously been published. The similarity in the shell-side characteristics of this baffle arrangement and two parallel single segmental baffle arrangements is demonstrated. A general relationship between the shell-side mass transfer performance and pressure drop was indicated by the data for all the baffle configurations examined.

Kinetic study on thermal decomposition of woods in oxidative environment

The purpose of this work is to gain knowledge on kinetics of biomass decomposition under oxidative atmospheres, mainly examining effect of heating rate on different biomass species. Two sets of experiments are carried out: the first set of experiments is thermal decomposition of four different wood particles, namely aspens, birch, oak and pine under an oxidative atmosphere and analysis with TGA; and the second set is to use large size samples of wood under different heat fluxes in a purpose-built furnace, where the temperature distribution, mass loss and ignition characteristics are recorded and analyzed by a data post-processing system. The experimental data is then used to develop a two-step reactions kinetic scheme with low and high temperature regions while the activation energy for the reactions of the species under different heating rates is calculated. It is found that the activation energy of the second stage reaction for the species with similar constituent fractions tends to converge to a similar value under the high heating rate.

Investigation of gas engine driven heat pump systems

Heat pumps are becoming increasingly popular, but poor electricity generating efficiency limits the potential energy savings of electrically powered units. Thus the work reported in this thesis concerns the development of a range of gas engine driven heat pumps for industrial and commercial heating applications, which recover heat from the prime mover, normally rejected to waste. Despite the convenience of using proprietary engine heat recovery packages, investigations have highlighted the necessity to ensure the engine and the heat recovery equipment are compatible. A problem common •to all air source heat pumps is the formation of frost on the evaporator, which must be removed periodically, with the expenditure of energy, to ensure the continued operation of the plant. An original fluidised bed defrosting mechanism is proposed, which prevents the build-up of this frost, and also improves system performance. Criticisms have been levelled against the rotary sliding vane compressor, in particular the effects of lubrication, which is essential. This thesis compares the rotary sliding vane compressor with other machines, and concludes that many of these criticisms are unfounded. A confidential market survey indicates an increasing demand for heat pumps up to and including 1990, and the technical support needed to penetrate this market is presented. Such support includes the development of a range of modular gas engine driven heat pumps, and a computer aided design for the selection of the optimum units. A case study of a gas engine driven heat pump for a swimming pool application which provided valuable experience is included.

Study of the deposition, properties and applications of electroless deposits containing particles

The deposition efficiencies of a number of electroless nickel and cobalt plating solutions were studied and in the case of nickel compared with a commercial plating solution Nifoss 80. At the optimum plating conditions (92ºC and pH 4.5) Nifoss 80 produced nickel layers most efficiently, the alkaline cobalt solution operated most efficiently at 90ºC and pH 9. The methods of producing compostte layers containing 2-3 µm carbide particles and chromium powder is described. Nickel and cobalt layers containing approximately 27% carbide particles, or 40% (Ni) and 30% (Co) chromium particles by volume were obtained. This value is independent of the particle concentration in the plating solution within the range (20~200 g/l). Hardness of the nickel. as deposited was 515 Hv, this was increased to a maximum of 1155 Hv by heat treatment at 200ºC for 5 hours in vacuum. Incorporation. of .chromium carbide particles resulted in a maximum hardness of 1225 Hv after heating at 500ºC for 5 hours in vacuum and chromium particles resulted in a maximum hardness of 16S0 Hv after heat treatment at 400ºC for 2 hours in vacuum. Similarly the hardness of cobalt as deposited was 600 Hv, this was increased to a maximum of 1300 Hv after heat treatment at 400ºC for 1 hour. Incorporation of chromium carbide particles resulted jn a maximum hardness of 1405 Hv after heating at 400ºC for 5 hours in vacuum and chromium particles resulted in a maximum hardness of 1440 Hv after. heat treating for 2 hours at 400ºC in vacuum. The structure of the deposits was studied by optical and scanning electron microscopy. The wear rate and coefficient of friction was determined by a pin and disc method. Wear rate and coefficient of friction decreased with increase in hardness. The wear resistance of the materials was also determined using a simulated forging test. Dies made of standard die steel were coated and the wear rates of the layers as deposited and after heat treatment were compared with those of uncoated tools. The wear resistance generally increased with hardness, it was 50-75% more than the uncoated die steel. Acetic acid salt spray test and outdoor exposure for six months was used to study the corrosion behaviour of the deposits and potentiodynamic curves plotted to find their corrosion potential. Nickel deposit exhibited less staining than carbide composite deposits and nickel-chromium deposits had the most noble corrosion potential.

Control of soundness and mechanical properties in aluminium-silicon-magnesium alloys

Previously, specifications for mechanical properties of casting alloys were based on separately cast test bars. This practice provided consistently reproducible results; thus, any change in conditions was reflected in changes in the mechanical properties of the test coupons. These test specimens, however, did not necessarily reflect the actual mechanical properties of the castings they were supposed to represent'. Factors such as section thickness and casting configuration affect the solidification rate and soundness of the casting thereby raising or lowering its mechanical properties in comparison with separately cast test specimens. In the work now reported, casting shapes were developed to investigate the variations of section thickness, chemical analysis and heat treatment on the mechanical properties of a high strength Aluminium alloy under varying chilling conditions. In addition, an insight was sought into the behaviour of chills under more practical conditions. Finally, it was demonstrated that additional information could be derived from the radiographs which form an essential part of the quality control of premium quality castings. As a result of the work, it is now possible to select analysis and chilling conditions to optimize the as cast and the heat treated mechanical properties of Aluminum 7% Silicon 0.3% Magnesium alloy.

Bio-fuel composition and method for manufacture of bio-fuel composition

The invention relates to a liquid bio-fuel mixture, and uses thereof in the generation of electrical power, mechanical power and/or heat. The liquid bio-fuel mixture is macroscopically single phase, and comprises a liquid condensate product of biomass fast pyrolysis, a bio-diesel component and an ethanol component.

Efficient purification of chromatin architectural proteins:histones, HMGB proteins and FKBP3 (FKBP25) immunophilin

A two-step process of high ionic strength lysis of chicken erythrocyte cell nuclei followed by cation-exchange chromatography has separated at very high yield all the histone and HMGB (high-mobility group B) nuclear proteins, except the less-soluble histone tetramers. Surprisingly high yields of the nuclear immunophilin FKBP3 (FKBP25) and Hsp70 (heat-shock protein 70) co-fractionate with HMGB1 and HMGB3. Furthermore, these proteins can be separated by anion-exchange chromatography. The purified nuclear proteins retain their native, post-translational modification (PTM) marks, including those associated with chromatin-fibre remodelling. These marks are intimately associated with the control of the cell cycle. The methods herein are therefore of value for targeting these and other nuclear proteins for future proteomic studies in healthy and diseased cells. This journal is © 2012 The Royal Society of Chemistry.

Change of composition and diversity of species and grassland management between different grazing intensity in Pannonian dry and wet grasslands

Investigations were carried out in wet and dry pasture. Coenological recordings were taken in three zones. The first zone (“A”) located 0-50 m near the stable, second zone (“B”) located 50-150 m from the stable, while the third zone (“C”) located farther than 150 m. We have carried out analyses of ecological and environmental factors and life form types. Based on our results for both dry and wet grasslands, quadrates of “A” zone were well isolated from the rest of the zones. Overgrazing, which involves considerable trampling, vanishes differences among vegetations, thereby promotes weed and disturbance tolerant rich vegetation. The lowest species number and diversity could be found here. Due to the nitrogen enrichment due to the constant presence of livestock, drier and less heat demanding habitat developed in the “A” zones, according to the environmental indicators. Because of the change in management, conservation and diversity values of “C” zone increased, however, according to nature protection values it underperformed compared to “B” zone. According to the sample area, wet grasslands from the sandy areas of Kiskunság, preserve nature protection values and grass composition better moving away from stables, due to less grazing pressure. Drier backgrounds tolerate stronger grazing pressure.