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The chemical method of solution deposition of Pb(Zr0·53Ti0·47)O3(PZT 53/47) thin layers on silicon involves shrinkage and stress development with heat treatment. Results are reported for shrinkage, as determined by in situ ellipsometry, and stress, measured by in situ laser reflectance, up to a maximum temperature of 700°C. Densification, thermal analysis, pyrolysis and crystallisation data are given and related to stress development as a function of sequential buildup of additional layers. For example, a residual tensile stress of around + 125 MPa was measured at room temperature for the first layer (inferred to be amorphous by the lack of XRD response). The stress magnitude decreased with increasing number of layers deposited. Observations are reported for the crystallisation of a fluorite phase on Si, and the formation of a lead silicate interfacial layer.

The chemical solution processing of dense insulating electroceramic thin layers is described with emphasis on the patterning of device structures. A review is presented for a wide range of patterning techniques and details are given for new additive methods based on soft lithography.

A new compound with a cubic structure, (Ba{sub 0.05}K{sub 0.95})BiO{sub 3}{center_dot}1/6H{sub 2}O (BKBO), was synthesized by electrochemical crystal growth using a rotating anode in molten KOH flux at 255 C. The BKBO crystal had the KSbO{sub 3} structure and belonged to space group Im{bar 3} (No 204) with Z = 12. Refinement of X-ray diffraction data at room temperature gave a = 10.0204(2) {angstrom}, V = 1006.1(1) {angstrom}{sup 3}, and R = 2.4% for 1465 unique reflections. Potassium, barium, and hydrated oxygen were found to occupy different sites in the tunnel structure. The electrical conductivity at room temperature was similar to the ionic conductor KBiO{sub 3}. BKBO decomposed to Bi{sub 2}O{sub 3}, K{sub 2}O, and BaO above 400 C.

Summary Through the use of theoretical and field examples, the potentially large errors associated with use of straight-line p/z decline (tank) analysis to assess gas in place (GIP) and reserves in tight-gas reservoirs are illustrated. The basic tank assumption that reservoir pressure gradients are small can be violated, even with long shut-in times. It is also demonstrated that a reasonably-straight-line p/z decline does not necessarily indicate that the reservoir behaves as a tank. The communicating reservoir (CR) model is presented as a simple, yet much more accurate, method of performing materialbalance calculations in tight reservoirs. The results of the application of the CR model to the Waterton gas field are used to illustrate the success and large impact that can be obtained by examining the pressure behavior more closely than simply plotting p/z.

Planar defects in the infinite-layer (Sr 1− x Ca x ) y CuO 2 structure are believed to be responsible for superconductivity with T c up to 110 K. In this work we present χ 2 minimization results to best fit a set of through-focal HREM images of such defects. Optimized atomic positions of the defect with an error bar of about 0.1Aare determined. The experimental parameters for simulated defect images such as sample thickness and objective lens defocus are determined by χ 2 fitting of the corresponding experimental HREM images of the matrix.

High dielectric ceramic thin films incorporated into microelectronic packaging will extend both the performance and functions of advanced microelectronic packaging. The low processing temperatures, excellent composition control and low capital manufacturing costs may make the sol-gel film preparation route a prime manufacturing method. For this technique to be a useful alternative to competing vacuum deposition methods, the interactions between the commonly employed packaging materials set and the Sol gel derived films must be understood. To integrate these films into applications the development of thin film stresses and resulting defects must be understood. In this study, we are examining the processing of sol-gel derived barium titanate thin films for use as integrated decoupling capacitors as our model system. Stress measurements are made by measuring curvature of thin film coated wafers as a function of temperature and time. The films exhibit both plastic and elastic behavior at different processing stages. These films are microscopically examined to observe the formation of microstructure including cracking and pinholes. By tailoring the thermal process to the viscoelastic film behavior high quality films may be produced.

Recent developments and understanding for the deposition and patterning of ferroelectric thin layers are reported. Two patterning techniques are described for mediated chemical solution deposition by: (i) microcontact printing (/spl mu/-CP), and (ii) micromolding in capillaries (MIMIC). These additive soft-lithographic methods are demonstrated for the patterning of sol-gel derived lead zirconate titanate (PZT) films on non-planar surfaces.

The evolution of stress is reported, as a function of processing conditions, for the chemical solution deposition of Pb(Zr/sub 0.53/Ti/sub 0.47/)O/sub 3/ (PZT) thin layers on silicon (Si). Shrinkage behavior was determined by in situ ellipsometry, and stress by in-situ laser reflectance measurements, to a maximum temperature of 700/spl deg/C. Densification, thermal analysis, pyrolysis and crystallization data are related to stress development as a function of the sequential build-up of multi-layered structures. A residual tensile stress of /spl sim/125 MPa was measured at room temperature for an amorphous 1-layer film. The magnitude of the stress decreased with increasing number of deposited layers. Observations are made for the crystallization behavior of pyrochlore on Si, and the formation of a lead silicate interfacial layer.

The deposition of ferroelectric thin layers from solution is described. Emphasis is placed on the powder-free ceramic processing method of polymeric sol-gel processing. Materials, include, PbTiO3, PbZrO3, Pb(Zr,Ti)O3, (Pb,La)TiO3, (Pb,La)(Zr,Ti)O3, BaTiO3, (Ba,Pb)TiO3 and other related materials, including LiNbO3. Processing parameters which affect the properties of ferroelectric thin layers are reviewed, including, solution chemistry and heat-treatment conditions. The results are interpreted in terms of the chemistry of precursors and gels, densification and crystallization behaviors, and interfacial reactions with the substrate and with the atmosphere during firing. Properties are reported for each class of materials, and compared with the properties of thin layers prepared by other chemical and physical methods, and with the properties of bulk ceramics and crystals. Of particular importance is the interaction of ferroelectric thin layers with various substrate materials, including semiconductors, for potential electrical and optical devices.

The published version of this paper is "Waterflood and CO2 Flood of the Fractured Midale Field," combined with and listed under paper number 22946. Abstract Typical EOR screening criteria suggest that naturally fractured reservoirs are poor candidates for miscible CO2 flooding. Despite this rule of thumb, the unusual geology and considerable EOR target of the fractured Midale field persuaded its owners to study implementation of CO2 flood technology. The 31,000 acre Midale field (Figure 1) is part of a trend of Mississippian carbonate reservoirs in southeastern Saskatchewan. Since 1962, the Midale Unit waterflood has recovered 20% of the 500 million barrels of original oil in place (OOIP); ultimate waterflood recovery is expected to be 24%. The reservoir section consists of a heavily fractured vuggy limestone (the "Vuggy") overlain by a less-fractured chalky dolomite (the "Marly"). Although naturally fractured, well productivities are modest, with average rates of 75–100 STB/D. In 1984 the Unit owners began a 4.4 acre tertiary miscible CO2 flood pilot. Important pilot data sources included residual oil measurements; single- and multi-well pressure transient tests; fluid analyses; time-lapse logging programs at injectors, producers, and observation wells; chemical, radioactive, halogen, and alcohol tracer programs; phase behavior studies focussing on wax-asphaltene deposition; geotomographic efforts to track flood fronts and displacement in situ; and core/CATSCAN studies of CO2 diffusion in Midale core. The $18.6 million pilot project was completed in 1989. Pilot results were history-matched and scaled-up with a state-of-the-art dual-porosity reservoir simulator. Field scale tertiary CO2 flood recoveries are predicted to be an incremental 20% OOIP, in line with expectations prior to pilot implementation. The high recovery is due to the unique interaction of the different geological layers in the reservoir. The bulk of the large tertiary target is trapped in the Marly dolomites high in the reservoir section.

Lead titanate fibers were formed from lead acetate and titanium isopropoxide by sol-gel methods. Additions of acids and chelating agents were used to influence hydrolysis and condensation reactions. A variety of solvents were examined, and the effect of conditioning treatments at elevated temperatures were investigated. Data are reported for the rheological behavior of viscous sols, fiber drawing ability, pyrolysis and crystallization of gels and fibers. Features of the ceramic microstructure are reported. A pyroelectric effect was measured for PbTiO3 fibers.

Hiroi et al. have recently reported the occurrence of superconductivity at a transition temperature of ~ 70 K in Sr2CuO3+δ. They observed a superstructure with lattice constants of Neutron diffraction studies on this compound by Shimakawa et al. indicate that the apical oxygen is fully occupied, whereas the oxygen in CuO2 plane is half occupied. If oxygen does not fully occupy in the conducting CuO2 planes, it raises doubts about our current understanding of superconductivity in the cuprates, which relies on full oxygen occupancy for the CuO2 planes.Recently, Han et al. observed a dependence of Tc on post annealing treatment of the high pressure synthesized Sr2CuO3+δ. They noticed that heating the sample to 300°C increased the Tc from 70 K to 94 K and that further heating to 450°C caused the sample to lose superconductivity.In order to investigate the structural and microchemical details of Sr2CuO3+δ, transmission electron diffraction, high resolution electron microscopy, and electron energy loss spectroscopy are employed.

Summary The considerable remaining oil target in the naturally fractured Midale field prompted a major reservoir and recovery mechanism study in the mid-1980's. Included in the study were the detailed evaluation of 20+ years of waterflood history and the implementation and analysis of a tertiary miscible CO2-flood pilot. The study showed that tertiary miscible flooding should not necessarily be precluded for naturally fractured reservoirs. Introduction The 500-million-bbl Midale oil field is part of a trend of large Mississippian oil accumulations located in southeastern Saskatchewan along the northern margin of the Williston basin. The field was discovered in 1953 and developed on 80-acre spacing. In 1962, Midale was unitized for waterflooding, with eighty-three 320-acre inverted nine-spot patterns (Fig. 1). The reservoir section in Midale consists of a heavily fractured vuggy limestone overlain by a less fractured chalky dolomite. Waterflood performance is dominated by these oriented vertical fractures, which typically are spaced 1 to 4 ft apart. Production wells located "on-trend" from injectors(aligned with the fractures) showed sharp early response to waterflood. In contrast, response of "off-trend" producers was smooth and delayed. Oil produced to date represents recovery of 20% of the original oil in place(OOIP); ultimate waterflood recovery is predicted to be only 24% OOIP. The current water cut in the mature operation is about 80% (Fig. 2). Although the reservoir is fractured, well productivities are modest, with average production rates of 75 to 100 STB/D-well. Typical EOR screening criteria suggest that naturally fractured reservoirs are poor candidates for miscible CO2 flooding. Despite this rule of thumb, the favorable reservoir geology combined with the substantial EOR target at Midale persuaded the field owners to study implementation of CO2-flood technology. A 4.4-acre tertiary miscible CO2-flood pilot was conducted during 1984–89. Field-scale waterflood and pilot-scale CO2-flood results were history matched with a dual-porosity reservoir simulator. Field-scale CO2-flood recoveries are predicted to be an incremental 20% OOIP. The high CO2-flood recovery results from the favorable interaction of the different layers within the reservoir. The bulk of the large tertiary target is trapped in the chalky dolomites in the upper reservoir section. Although most of the CO2 is injected into the underlying heavily fractured limestones, gravity forces cause the CO2 to rise and come in contact with the oil in the dolomites. Based on pilot results and simulation studies, a $40-million commercial-scale CO2 flood began in Feb. 1992 in 10% of the unit. Geology The 4,600-ft-deep, gently dipping productive carbonates are overlain and underlain by impervious anhydrite beds.1The productive interval typically consists of a limestone (the Vuggy) overlain by a dolomite (the Marly), as shown in the type log in Fig. 3. The Marly zone has a layered geometry with good lateral continuity between wells. The Vuggy is less layered and more laterally discontinuous. The average gross thicknesses for the Vuggy and Marly zones are 40 and 30 ft, respectively; reservoir development is 20 ft in the Vuggy and 10 ft in the Marly. The reservoir is quite consistent in total thickness, varying from 60 to 80 ft across the majority of the unit. Internally, however, the Vuggy/Marly thickness ratio does vary considerably. The Vuggy zone contains two distinct rock types, intershoal and shoal. The intershoal Vuggy is present over the entire unit, while shoals have limited areal extent. Indeed, the majority of the unit is devoid of shoal Vuggy. However, where shoal Vuggy does exist, it dominates performance because of its high permeability. Intershoal Vuggy consists primarily of peloidal and bioclastic packstones containing mostly interparticle porosity. The shoal Vuggy consists of peloidal grainstones that display visually dramatic vugular and interparticle porosity. Despite these large pores, porosity values in the shoal and intershoal are very similar, ranging from 10% to 15%. Typical intershoal permeabilities are 1 to 10 md, with shoal permeabilities an order of magnitude higher. The Marly zone consists primarily of dolomitic wackestones and mudstones, with the mudstones forming the best reservoir rock. Porosity, which ranges from 20% to 35%, is predominantly intercrystalline with secondary amounts of pinpoint vuggy porosity. Marly permeability ranges from 1 to 10 md.

The feasibility of growing single crystal Bi 2 WO 6 by the hydrothermal method is reported. Single domain crystals (∼1mm) were readily grown at 400°C, well below the disruptive high temperature phase transformation, from 2N aqueous KF solutions. Data is given for X-ray diffraction and hot-stage microscopy observations. The significance of preparing strain-free, single domain, highly acentric polar crystals for new device applications is discussed.

The preparation of solid solution perovskite 70% Pb(Fe 1 2 Nb 1 2 ) O 3 -30% Pb(Fe 2 3 W 1 3 ) O 3 is described for use as a thick film capacitor on ceramic chip carriers. The limited densification at the temperature range of interest (850 – 900°C) requires the addition of a sintering aid. It is shown that a small addition of PbO(7 vol.%) is sufficient to promote densification of this material and maintain a dielectric constant exceeding 4000 for a fired thick film. Other electrical and physical properties of this material are described.

A quantitative analysis for the measurement of solute water (SOL) in the presence of polymer water (POL) by dielectric measurements was developed. Sucrose, starch and their mixtures at known moisture content and water activity (aw) were measured. Dielectric constant (K) was relatively insensitive to polymer water (POL) but very sensitive to capillary water (CAP). K was very sensitive to the amount of water in a supersaturated sucrose solution but not to dilution of the saturated solution. A given increment of solute water (SOL) in a mixture gave the same K over the whole aw range, independent of sorbent composition. A model was developed to quantitate SOL in a mixture with POL by measuring K at 1000 KHz.

The use of ROM (ready only memory) with Motorola M6800 microprocessor systems is made unnecessary. The contents of RWM (read write memory) are loaded from a central computer, and the microprocessors are then directed to start, stop or change programs from the central computer. Macquarie University has a Hewlett-Packard 2100S computer running a number of terminals used to control experiments, with data transfer in either direction at speeds of up to 300 k words per second. Microprocessors can be attached to these terminals and loaded with M6800 machine language programs which are stored on the disc memory of the central computer. Commands can then be issued from the central computer to control the microprocessors. The M6800 machine language is produced by a crossassembler which runs on the HP 2100S. This program accepts M6800 assembler language and generates M6800 machine language which is stored on disc. Programs can then be selected from disc and sent to RWM of the microprocessors, and execution commenced.

In a long-lifetime dewar, heat loads to the cryogen fall into two distinct categories: parasitic heat leak (i.e. conduction and radiation from the vacuum shell) and internal heat loads (i.e. electrical power dissipation and telescope aperture heating in the case of cooled telescope systems). To accommodate launch loads, the cryogen tank support system of a spaceborne dewar must be stout, and heat conducted from the vacuum shell through the supports can have a large influence on cryogen loss rate. Sophisticated support systems using low conductivity composite materials for thermal optimization have consequently been developed. The most thermally efficient support system used to date in flight hardware is fibreglass/epoxy tension straps. To provide even better thermal efficiency than straps, various attempts have been made over the last two decades to develop dual support concepts in which a primary support reacts launch loads and a smaller, more thermally efficient support then holds the cold assembly in place after launch. This Paper compares predicted dewar performance for several cases using both tension straps and the best developed dual support approach, passive orbital disconnect struts (PODS). Results show that cryogen loss rates are very similar for both systems. Straps provide a slight advantage for storage of lighter cryogens such as helium and hydrogen, and PODS are slightly better for heavier cryogens such as nitrogen and oxygen. The PODS system is more complex than straps, and a flightworthy design does not yet exist. The performance of a flight system using straps is at this time more predictable than one using PODS.

The adsorption of thiocyanate anion on mercury was measured by means of a new electrochemical technique,chronocoulometry. Extensive adsorption of Hg(SCN)2 was also discovered and the influence of free thiocyanate ion on this adsorption was evaluated. An interesting unexpected result of this work was the demonstration of an apparent negative integral double-layer capacitance for mercury over part of the potential range investigated.

Argon and nitrogen adsorption isotherms at −196°C were determined on various porous and nonporous silicas, which had been well characterized in previous studies. The corresponding isotherms on each nonporous solid run nearly parallel over the middle range of p p 0 , but the isotherms on the microporous silica cross at p p 0 ∼ 0.1 . Surface areas have been calculated from the isotherms by means of the BET method and the α s -method. To apply the latter method to the argon isotherms it has been necessary to express the new standard adsorption data in the reduced α s form, as has been done previously with nitrogen. Deviations of the α s -plots from linearity are explained in terms of micropore filling and capillary condensation. In the absence of micropore filling, the surface areas calculated from the slope of the α s -plots are in good agreement with the corresponding BET -areas, provided that the cross-sectional area of argon in the BET monolayer is taken as 18.2 A 2 . Micropore filling causes a distortion of the isotherm in the BET range, the effect being greater with argon than with nitrogen and resulting in a decrease in the apparent cross-sectional area of argon.

Adsorption isotherms of argon, nitrogen, and water vapor are reported on well-characterized nonporous aluminas and silicas, along with sorption isotherms of water vapor on various calcined chromium oxide gels. The argon and nitrogen isotherms are analyzed by means of the α s -method (a modification of the t -method of Lippens and de Boer). With low-area samples of alpha-alumina the argon α s -plots are linear in the multilayer region of the isotherm whereas the corresponding nitrogen α s -plots show marked departure from linearity. This, together with significant differences in the isosteric heats and in the BET C values, indicates that the nitrogen monolayer is localized to such an extent that the structure of the multilayer is significantly different from that formed on low-temperature aluminas and hydroxylated silicas. It is suggested that the nitrogen molecule occupies an average area of about 18 A 2 in the localized monolayer instead of the usual value of 16.2 A 2 in the close-packed monolayer. Self-consistent values of surface area are obtained if the molecular cross-sectional area of argon in the BET monolayer is also taken as 18 A 2 for all the nonporous oxide and hydroxylated oxide surfaces. The water isotherms, expressed on a unit area basis, show a large variation from one type of solid to another. Five different mechanisms are identified for the sorption of water vapor, two of which involve penetration below the surface.

Reported here are polarocaloric (electrocaloric) measurements of a ceramic specimen of lead zirconate modified with Ti/sup 4 +/ and Sn/sup 4 +/. Temperature changes as large as 2.0 /sup 0/K were recorded. The measured effect agrees with a thermodynamic calculation which utilizes the temperature dependence of polarization versus electric field.