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Multivariate calibration models are of critical importance to many analytical measurements, particularly for spectroscopic data. Generally, considerable effort is placed into constructing a robust calibration model since the model is meant to be used for extended periods of time. A problem arises, though, when the samples to be predicted are measured on a different instrument or under differing environmental factors from those used to build the model. The changes in spectral variations between the two conditions may make the model invalid for prediction in the new system. Various standardization and preprocessing methods have been developed to enable a calibration model to be effectively transferred between two systems, thus eliminating the need for a full recalibration. This chapter presents an overview of the different methods used for calibration transfer and a critical assessment of their validity and applicability. The focus in this overview is on methods for transfer of near-infrared spectra, but the methodology is widely applicable.

Anecdotal evidence suggests that a disliked food can act as a contaminant to liked food during childhood. While this has been investigated in an infant sample, the current paper presents the first study to investigate this phenomenon in a sample of young children (4 years 5 months-6 years 1 month old, N=30). Children were shown a liked food at different stages of being contaminated by a disliked food. At each stage, the children were asked to rate their willingness to consume the liked food on a 3-point hedonic scale. The data show that children reduce their rating of a liked food once it has been in contact with a disliked food, in comparison to a like-like combination control measure. The data also show that girls show greater sensitivity than boys to this form of contamination and that the younger children are more likely to show a prolonged response (rating of the liked food does not return to the unadulterated level) than the older children in the sample. Several possible reasons for these findings are discussed including disgust, inferred distaste and associational contamination.

This study was conducted to examine whether disliked foods can act as contaminants to liked foods during infancy. Participants (aged 18–26 months, N = 18) were offered a liked food that was touching a disliked food, on the same plate. Their response to this liked food was compared to the infants’ response to a control condition; a liked food touching a second liked food. The data show that children were less likely to eat a liked food touching a disliked food, than a like-like control. Of the 18 infants tested, eight children either wanted the disliked food completely removed from the plate, or would not consume the liked food at all ( N = 2) once it was ‘contaminated’ by the disliked food. This study was the first to test the anecdotal reports that disliked foods can act as contaminants during infancy and the data offer some support for the hypothesis that disgust may influence the acceptance of food during early childhood.

A simple scenario and modelling approach to farm design was used to investigate the potential for improving on-farm conservation outcomes in three mixed grain-livestock farms in eastern Australia. With an increasing emphasis on multiple benefits from land management in agricultural landscapes, and current policy frameworks governing natural resource management and agriculture in Australia, much of the cost of conservation is expected to be borne by farmers. This is especially so in terms of production opportunity costs, which go largely unrecognised (and uncosted) in landscape planning. Simple landscape ecology design principles were applied to existing farm configurations in a scenario process to improve protection and connectivity of natural parts of the landscape, and the direct (infrastructure) and indirect (loss of production) costs were calculated. A 3 stage approach was taken to develop scenarios: (1) identify major threatening processes and mitigating actions to prevent further decline in natural resources; (2) identify opportunities for enhancing landscape configuration in respect of the landscape ecology principles outlined below; and (3) explore agricultural opportunities to offset financial losses to conservation. Depending on the specific agricultural activity mix and ecological condition of farms, small changes to the production base can have large impacts on farm enterprise profitability. Modelled economic impacts show that there are substantial opportunity income losses from applying conservation-based scenarios, and that there are limited opportunities to offset these with changed farming practices that do not create other environmental problems.

The influence of the fuel to oxidant ratio on the ageing behaviour of the magnesium–strontium nitrate pyrotechnic system in the presence of water vapour has been investigated by isothermal microcalorimetry in conjunction with chemical and thermal analysis measurements. The major products of ageing were identified as magnesium hydroxide and strontium nitrite. Measurement of the ratio of the amount of magnesium hydroxide formed to that of strontium nitrate reacted has shown that for compositions containing from 10 to 60% magnesium, a major component of the ageing process could be represented by the equation 3Mg + Sr(NO3)2 + 4H2O → 3Mg(OH)2 + Sr(NO2)2 + H2. DSC studies have confirmed that the formation of strontium nitrite during ageing has a significant influence on the high temperature pyrotechnic reaction between magnesium and strontium nitrate.

The ageing behaviour of a pyrotechnic composition containing equal parts by mass of magnesium and strontium nitrate has been followed by isothermal microcalorimetry. The measurements were carried out on the samples at 50 °C and 65% relative humidity in air using closed ampoules. The results have been compared to those obtained for magnesium powder under the same conditions. Following an initial induction period, the pyrotechnic compositions reacted at a much faster rate than magnesium powder alone. The main reaction products were found to be magnesium hydroxide and strontium nitrite; the amounts formed have been correlated with the cumulative heats of ageing. In addition, the influence of the ageing process on the pyrotechnic reaction has been studied by high temperature differential scanning calorimetry (DSC) and by modulated temperature DSC.

The ageing behaviour of a pyrotechnic mixture of magnesium and potassium nitrate has been followed at 50 °C and 65% relative humidity by isothermal heat flow calorimetry. Measurements have been carried out with samples in air and in an inert atmosphere. The main reaction product was found to be magnesium hydroxide. This has been determined quantitatively by thermogravimetry and the amount formed correlated with the measured cumulative heat of ageing. The results have been compared with those obtained for magnesium powder studied under the same conditions. In addition the influence of the ageing process on the pyrotechnic reaction has been studied by high temperature differential scanning calorimetry under ignition conditions and modulated temperature differential scanning calorimetry.

The aim of this study is to demonstrate the potential of coals as a low-cost reactive barrier material for environmental protection applications, with the ability to prevent leaching of toxic Cr(VI) and other transition metals. Depending upon the type of ion and the surface functionalities, the uptake can involve ion sorption, ion exchange, chelation and redox mechanisms with the surface functionalities being considered as partners in electron transfer processes. The capacity for Cr(VI) uptake of low rank coals and oxidized bituminous coals has been found to lie within the range 0.2–0.6 mM g −1 . Air oxidation of bituminous coals can increase their Cr(VI) removal capacities. The effect of air oxidation of coals on uptake capacity was more pronounced for Cr(VI) than Cr(III), but less than for Hg(II) and the other ions (Ca 2+ , Ba 2+ , Zn 2+ , Cd 2 ) investigated. As previously found for Hg(II), redox mechanisms play an important role in Cr(VI) uptake, with sorption of the resultant Cr(III) being aided by the functionalities arising from oxidation of the coal surface. In acidic media, much of the resultant Cr(III) is exchanged back into solution by hydrogen ions, but some of the sorbed chromium is irreversibly bound to the coal. The reduction of Cr(VI) alone is often considered a satisfactory solution in view of Cr(III) being essentially non-toxic.

The organic structures in sapropels sampled from two cores obtained at known locations beneath the southern Black Sea have been characterised. Fluorescence petrography shows the sapropels to occur as layers of impure alginite, ∼50 μm thick, within Unit 2 of the sediments. Solid state 13 C NMR indicates the bulk chemical structures to be very similar to those in an immature Type 1 kerogen (lamosite) oil shale with an aromaticity of ∼0.2. Consistent with the immaturity of the sapropels, which are between 3000 and 7000 years old, temperature programmed reduction showed aliphatic and aromatic sulphides to be the major organic sulphur forms. Alkanes formed from phytoplankton lipids, alkyl benzenes, alkyl naphthalenes and some phenols dominated the mix of volatile compounds identified by pyrolysis-gas chromatography/mass spectrometry. About half of the sapropels remained as an involatile, tarry residue after pyrolysis. The structure of the sapropels is consistent with their formation resulting from marine phytoplankton with only small terrigeneous inputs. Future catagenesis may be expected to decarboxylate the lipids, increase the aromaticity and to dry and compress the muds to form a source rock.

Contrast matching small angle neutron scattering has been performed on a series of Argonne coals using H2O/D2O mixtures using short contact times between the coal and liquid. Calculations of the neutron scattering densities of the coals based on their 'formulae' and helium densities are discussed. The results of the CM-SANS are given and it is shown that the scattering from the scattering from the non-contrast-matched samples is unreliable. It is shown that porosity in coals is effectively determined by the presence of water and that porosity levels decrease with increasing rank.

High oil yields (ca. 60% both daf and carbon basis) with relatively low hydrocarbon gas yields can be achieved for coals and oil shales in fixed-bed pyrolysis at high hydrogen pressure (hydropyrolysis, 15 MPa) with relatively fast heating and a suitable dispersed catalyst, such as sulphided Mo or Fe. This article reviews the application of hydropyrolysis to biomass and its adaptation as an analytical technique to specify organic sulphur forms and to release covalently-bound biomarker hydrocarbons for coals and petroleum source rocks. Results for cellulose, eucalyptus wood and sugar cane bagasse demonstrate the potential of hydropyrolysis for producing bio-oils with much lower oxygen contents than by traditional pyrolysis processes. The inherent drawbacks with temperature programmed reduction (TPR) for specifying the organic sulphur forms in sedimentary organic matter in that (i) thiophenic sulphur has largely been undectable and (ii) sulphides interconvert readily into thiophenes have been overcome by the use of the well-swept fixed-bed hydropyrolysis reactor operating at 15 MPa. The application of high pressure TPR to pyrite-free bituminous coal and a type-IIS kerogen is described. To illustrate the ability of hydropyrolysis to release covalently-bound biomarker hydrocarbons from sedimentary organic matter, the yields and conformations of the hopanes and steranes released from a type I kerogen are presented.

Urbanization is escalating in many coastal areas of the US and is associated with deteriorating water quality. Often the associated changes in land use result in an overabundance of nutrients and other types of pollution entering ground and surface waters. It is important that we understand biogeochemical transformation processes on urbanizing watersheds if we are to develop management practices that can improve nutrient attenuation on the landscape. In this study denitrification capacity was estimated for two watersheds with residential and resort land uses on Kiawah Island, South Carolina. Potential for soils and sediment to reduce nitrogen (N) in runoff was estimated, and ways to improve denitrification capacity were tested. Background denitrification capacities (ambient) were substantially less than the potential short-term capacity (nutrient enriched) that ranged from 0.03 to 1.82 nM nitrous oxide (N2O) gdw-1 h-1 in soil and 0 to 2.48 nM N2O gdw-1 h-1 in pond sediments. Denitrification rates were considerably higher near the soil surface than at the water table, rates were stimulated by adding NO3- to the surface but not by adding it to the subsoil, and added glucose did not affect rates. Potential long-term rates were explored using soil amendments and 340 hour incubations. Denitrification capacity was stimulated with added nitrate (NO3-) and with added NO3- plus carbon (C) in the form of glucose and wood fiber, but denitrification rates dropped to zero after addition of only glucose and wood fiber to soil. This suggested that heterotrophic microbes grew on the carbon substrate and reduced N availability through immobilization, and this low N availability was confirmed for C amended soil. These results suggest that 1) immobilization may be an important process in the removal of anthropogenic NO3- from stormwater runoff, 2) the N processing efficiency of a landscape can be sustained with high soil organic matter (SOM) content, as on forested watersheds, and 3) N processing efficiency can be improved on SOM depleted soils by incorporating wood fiber into the soil to provide substrate for microbial activity.

In order to probe the formation of sulfur- and nitrogen-containing gases during the pyrolysis and combustion of coals and other solid fuels, non-softening model substrates are required. In this respect, phenol-formaldehyde (PF) resins are ideal since they readily facilitate the incorporation of individual heteroatomic functions into a highly crosslinked matrix. A series of sulfur- and nitrogen-containing co-resites have been prepared using phenol with, as the second component, thiophene, dibenzothiophene, diphenylsulfide, benzyl phenyl sulfide, thioanisole, 8-hydroxyquinoline and 2-hydroxycarbazole. A mole ratio of 3 : 1 (phenol: heteroatom-containing component) was adopted in order to ensure that a reasonably high degree of crosslinking was achieved. Resoles containing diphenyldisulfide were also prepared but, due to the comparable bond strengths of the S-S and C-O linkages, a curing temperature of only 130 degrees C was used to avoid cleavage of the disulfide bond. The virtually complete elimination of ether and methylol functions from the resoles by curing at 200 degrees C was monitored by solid-state C-13 nuclear magnetic resonance (n.m.r.) spectroscopy. The resultant resites were also characterized by sulfur K-edge X-ray absorption near-edge structure (XANES.) spectroscopy, X-ray photoelectron spectroscopy (X.p.s.) and differential scanning calorimetry (d.s.c.). Simple air oxidation was found to selectively convert the aliphatic-bound sulfur to a mixture of sulfones and sulfoxides. Applications of the resites in fuel science are described.

For the well-swept fixed-bed reactors used in temperature-programmed reduction (TPR) to specify the organic sulfur forms present in coals and kerogens, calibrants must neither melt nor evaporate before the onset of thermal decomposition. In this respect, nonmelting silica-immobilized substrates are suitable with the Si-O-C linkage being stable up to ca. 500 °C. Silica-immobilized samples of dibenzothiophene, diphenyl sulfide, phenyl benzyl sulfide, and thioanisole have been synthesized and noncatalytic tests have been conducted in atmospheric and high-pressure TPR reactors. The characteristic reduction temperatures of the non-thiophenic compounds investigated are well resolved from that of dibenzothiophene for both techniques and the results have validated previous findings by TPR on coals. The use of high hydrogen pressure (150 bar) lowered the reduction temperatures substantially. The H 2 S recoveries from the atmospheric experiments are low suggesting that, for the non-thiophenic compounds, secondary reactions occur yielding refractory thiophenes which are not detected. Although sulfur recoveries are greatly improved, such reactions are still evident with 150 bar hydrogen pressure especially in the case of the phenyl benzyl sulfide, possibly as a consequence of the high surface coverages used. Insights into the retrogressive chemistry occurring for the immobilized phenyl benzyl sulfide have been provided from GC-MS analysis of hydrolyzed TPR residues obtained at different temperatures, and from vacuum pyrolysis experiments conducted as a function of surface coverage.

Ion implantation is now a well established technique for the production of optical waveguides for integrated optics applications. However, in some materials, such as lithium niobate, it leads to anomalous optical properties in the waveguiding region. We have investigated the structure of the waveguide and the damaged region in ion-implanted lithium niobate by carrying out complementary X-ray topography and near surface X-ray diffraction on etched crystals. The results indicate radiation enhanced annealing in the waveguide itself and the upper region of the substrate, as well as a high degree of amorphisation in the damaged layer.

The origin of anomalous refractive index values in ion implanted optical waveguides in some crystalline materials has been an outstanding problem for several years. By use of complementary X-ray edge-topography and Raman microprobe imaging we have found evidence that changes in the dislocation density after implantation correlate with changes in the dynamic response of the lattice to light. This implies that the effects of reduced dislocation density may be related to the origin of the refractive index anomalies, possibly as a result of strain relief. Further support for this hypothesis comes from the fact that the original bulk dislocation density is recovered throughout the crystal by annealing to the temperature at which the refractive index anomalies are lost.

Calcium aluminate glass fibers offer major new opportunities in transportation, infrastructure composites and new infrared sensor applications. They possess a higher modulus than S-glass, an advantage that can yield major weight and energy savings in car, aircraft and aerospace composites, or stiffer composite parts in emerging bridge and construction markets. Their superior alkali resistance is an important advantage in cement composites. They also possess sapphire-like infrared transmission, a property that is obtained at a fraction of the cost of single crystal sapphire fibers. Quaternary non-silica calcium aluminates with 40–50% alumina have high melt viscosities ( ⪢10 Pa s ). Experimental fibers were obtained by potentially commercial processes (up-drawing from supercooled melts and down-drawing from performs). Binary compositions with >50% alumina have low viscosities ( ⪡10 Pa s ). Glass fibers were obtained by an experimental process (inviscid melt spinning) from melts with up to 81% alumina. Infrared optical aluminum tellurite fibers were obtained from supercooled melts. New glass theory is applied. Melt viscosity and glassy modulus are rheology controlled and their magnitude is due to differences in size, shape and orientation of nanocrystalline domains. Not surprisingly, the silicate and aluminate glass (or glass ceramic) fibers with the highest modulus (160–180 versus 69 GPa for E-glass) had the most pronounced nanocrystallinity.

Molecular Ecology Resources Primer Development Consortium: et al., This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium dahliae, Wasmannia auropunctata, and Zygochlamys patagonica. These loci were cross-tested on the following species: Chaetodon baronessa, Falco columbarius, Falco eleonorae, Falco naumanni, Falco peregrinus, Falco subbuteo, Didelphis aurita, Gracilinanus microtarsus, Marmosops paulensis, Monodelphis Americana, Odontesthes hatcheri, Podocarpus grayi, Podocarpus lawrencei, Podocarpus smithii, Portunus pelagicus, Syngnathus acus, Syngnathus typhle,Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvauceli and Verticillium albo-atrum. This article also documents the addition of nine sequencing primer pairs and sixteen allele specific primers or probes for Oncorhynchus mykiss and Oncorhynchus tshawytscha; these primers and assays were cross-tested in both species.

Electric impedance (EI) spectra (1kHz-20Mhz) of isolated polymorphonuclear leukocytes and red blood cells were recorded by positioning individual cells between pairs of metal electrodes in slender rectangular channels (/spl sim/40 10/sup -12/ m/sup 2/ cross-sectional area). The present study was designed to demonstrate that cell type, viability and dielectric properties can be discerned on the basis of raw micro-EI spectral data. Each micro-EI MEMS device was tested to quantify the frequency-dependent impedance of the electrode-electrolyte interface at the experimental current density. Sensitivity of the technique to changes in sample properties was tested by filling the recording zone with a variety of materials and cells with known dielectric properties. Small changes in cell media ionic concentration and cellular dielectric properties were quantifiable by analysis of EI data. Results further show that micro-EI signatures of the device when loaded with red blood cells (RBCs) vs. polymorphonuclear leukocytes (PMNs), or vital vs. non-vital PMNs were significantly different thus allowing cell identification on the basis of spectral signatures.

World Renewable Energy Congress III - Climate Change, Energy and the Environment -- SEP 11-16, 1994 -- READING, ENGLAND, WOS: A1994PU94700017, To assess the effects of mass transfer and hydrogen pressure on the oil yield and quality from cellulosic biomass, fixed-bed pyrolysis (atmospheric pressure) and hydropyrolysis experiments at temperatures between 400 and 650 degrees C have been conducted on sunflower bagasse and pure cellulose. The Euphorbia Rigida was extracted with n-hexane and methanol to remove low molecular mass terpenoids and saccharides so as to elucidate the extent of oil formation and aromatisation from the cellulosic structure. In contrast to coals and oil shales, oil yields from the sunflower bagasse were found to be largely independent of particle size ( 50 bar) only gave rise to relatively small increases in oil yield but, expressed on a carbon basis, these increases are much greater due to the reduced the oxygen contents of the oils.

Bronchography is seldom recommended today to localize radiographically and bronchoscopically occult bronchogenic carcinoma. We report a case in which bronchography promptly localized such a tumor that had been occult to multiple bronchoscopies and chest computed tomograms (CTs). The patient is free of recurrence 32 months after lobectomy. Bronchography should be considered when bronchoscopies and CT fail to reveal a radiographically occult carcinoma.

In vitro killing rates for levofloxacin and ciprofloxacin for six strains of Streptococcus pneumoniae were determined by the time-kill method outlined by the NCCLS. Both drugs were bactericidal at concentrations of two and four times their respective minimum inhibitory concentrations (MICs). Levofloxacin achieved a 99.9% kill on average in 1 hour more rapidly than ciprofloxacin. Post-antibiotic effect was also determined for both drugs against the same six strains. A post-antibiotic effect for a mean of 1.2 and 1.0 hours was observed for levofloxacin and ciprofloxacin, respectively. The latter means were not considered significantly different.

The authors show that the incorporation of patterned spatial mixing between classes and within class texture can greatly increase the fidelity of synthetic image generation (SIG) for both visual assessment and quantitative analysis using multi/hyperspectral analysis tools. We have demonstrated how within and between classes, spatial/spectral variability can be introduced into a SIG model that includes a full radiometric processing chain. Further effort in this area needs to focus on exercising this capability for specific scenarios and evaluating the quantitative fidelity of the resulting images.

Publisher Summary This chapter discusses the effects of iron (Fe) and molybdenum (Mo) catalysts in hydropyrolysis and temperature programmed reduction, a cured phenolic co-resin prepared from phenol and 4-hydroxy diphenylmethane and a polystyrene–divinylbenzene network. The conversion characteristics of these models are compared with those of a bituminous and a low-rank coal. Iron and molybdenum compounds are the subject of precursors for sulphided catalysts for both coal liquefaction and hydropyrolysis. Iron at relatively low concentrations is less effective than sulphided Mo. For low-rank coals at high pressure, catalysts only increased tar yields typically by less than 10% daf coal, but without a catalyst, the tar yields of 40–50% are appreciably higher than for bituminous coals. Although rapid heating is used in process situations, slow heating is being applied in temperature programmed reduction (TPR) to specify organic sulfursulfursulfur forms in coals. The use of model compounds is widely used to probe reaction pathways in coal liquefaction. The effects of Fe and Mo catalysts on bond scission and product distribution during hydropyrolysis is investigated using two solid phase models––namely, a cross-linked polystyrene–divinylbenzene and a 4- hydroxydiphenylmethane-containing phenolic resin.

Chemical analysis in flowing solution is popular for automation of classical methods. However, most of the classical methods are not specific enough for direct multicomponent analysis of simple mixtures. This research project has the goals of study of rapid multicomponent analysis of transient species in flowing media, and investigations of chemical reactions at interfaces and of effects of competition on distribution of products from interfacial reaction. This report summarizes work done over the past 4.5 years; support has been terminated.

In view of the interest in catalytic hydropyrolysis and suitable dispersed catalysts, the uptake of palladium has been investigated using three different coals, namely, North Dakota and Mequinenza lignites and Gedling high-volatile bituminous coal

In this communication, the temperature-programmed reduction with on-line mass spectrometry has been conducted on the series of four fenolic resites (cured resoles) containing different sulfur functionalities in a TGA apparatus to ascertain whether the release of SO 2 is dependent primarily on sulfur functionality or whether other factors, particularly the concentration of volatile matter and chemistry involving the interconversion of sulfur forms, are also important for macromolecular systems

Thin layers of cobalt and Co/ZnO muitilayers have been deposited by metal-organic chemical vapour deposition and characterized by a range of structural and magnetic techniques. In general, the samples exhibited an overall in-plane magnetic anisotropy, the strength of which decreased with decreasing cobalt layer thickness. A buffer layer of ZnO was found to decrease the strength of the anisotropy with respect to a film of the same thickness deposited onto glass.

The application of convolution potential voltammetry to questions of metal complexation is described. Theoretical relations are derived to show that the stability constants may be directly related to the shift in the peak potential of the semiderivative wave, provided the complexes are labile. Equations are also given for inert and quasilabile complexes. Stability constants for the PbClx and CdClx systems are reported, illustrating the use of convolution techniques with linear scan voltammetry and with linear scan anodic stripping voltammetry. Advantages of convolution techniques are discussed.

Progres realises aux Etats-Unis dans le domaine du controle non destructif des chaudieres a vapeur

Reactions of chromium pentafluoride, CrF5, with some Lewis acids and bases have been studied and the reaction products have been characterized by infrared and Raman spectroscopy. CrF5reacts with the bases CsF and NO2F to give CsCrF6 and NO2CrF6, respectively. The Lewis acid, SbF5, reacts with CrF5 to give the adduct CrF5·2SbF5, which should be formulated as CrF4Sb2F11 on the basis of spectroscopic evidence. This compound is a strong oxidizing agent, reacting with O2, Xe and C6F6 to form, respectively, O2(CrF4Sb2F11), Xe(CrF4Sb2F11)2 and C6F6(CrF4Sb2F11). It was observed that O2(CrF4Sb2F11) reacts with C6F6 and IF5 to form C6F6(CrF4Sb2F11) and IF4(CrF4Sb2F11), respectively.

In this paper selected literature and experiments performed at the University of Illinois pertaining to the potential use of plasma-sprayed ceramic-coated metal systems as implant materials are reviewed. The nature of the coating-substrate bond is discussed. Adhesive and/or cohesive failure with regard to alumina-coated type 316L stainless steel and Ti-6Al-4V ELI substrates in physiological media is treated as a rate process. The issue of biocompatibility is addressed. Strategies for overcoming the problems uncovered are indicated.

A NEW PREPARATION OF PEROXYDISULFURYL DIFLUORIDE S.D. Brown and G.L. Gard Department of Chemistry Portland State University Portland, Oregon 97207 ~ece~ed27Au~st1974) Cady and Dudley (i) first reported the preparation of peroxydisulfuryl difluoride ($206F2) via the catalytic fluorination of SO 3 with F 2 over AgF 2 at i00 °. More recently it was shown that XeF 2 will react with SO 3 to form $206F 2 (2). We now wish to report another route to $206F 2. Chromium pentafluoride reacts quantitatively with SO 3 according to the following equation: CrF 5 + 5S03 ) $206F 2 + Cr(SO3F) 3 Pure $206F 2 is removed from the reaction mixture at -22 ° . Cr(SO3F)3, which has not been previously reported, is an amorphous light green solid soluble in DMSO. The infrared spectrum was measured neat between KRS5 windows and is listed along with its assignments in Table I. TABLE I Infrared Spectra of Cr(SO3F) 3 Band (cm -I) Approximate Assignment

Accurate determination of stability constants for actinides is necessary for prediction of transport properties of nuclear waste. Since solubilities are generally low, these stability constants must be determined in dilute solution. We have used cw and pulsed laser-induced photoacoustic spectroscopy to study trace neodymium (III) in water and in aqueous carbonate media; the coordination chemistry of Nd(III) is similar to that of many actinide species, so that Nd(III) is a good model system.

High level nuclear waste is commonly incorporated into glass for disposal. Therefore the long term aqueous durability of the waste glass is important. The leaching behavior of three simulated nuclear waste glasses (AH10, AH165, and Frit 165) and a natural glass (tektite) were examined using nuclear reaction analysis, leachate solution analysis, and microscopy. The three simulated waste glasses developed hydrated layers which increased in thickness by t/sup /1/2//. The hydrated layer in Frit 165 reached a constant thickness of about one micron. Alkali were preferentially removed from the Frit 165 and AH10. The tektite corroded by slow uniform dissolution. 94 refs., 68 figs., 13 tabs.

The overall project objective is to establish and confirm by test the viability of a steam turbine rotor component lifetime prediction system that is based on finite element thermo-elastic stress analysis and fracture mechanics, and that uses details of field NDE inspection results as input to the calculations. The effort to date has been composed of four tasks contracts. These tasks are: lifetime prediction analysis system, nondestructive evaluation, destructive tests, and material mechanical properties measurements. The automated Steam Turbine Rotor Analysis Program (STRAP) was developed to facilitate the prediction of rotor lifetime given the duty cycle of the turbine and the results of ultrasonic examination from the rotor bore. STRAP consists in part of a preprocessor code that generates the boundary conditions and finite element mesh for transient and steady-state temperature and stress analysis employing the ANSYS general-purpose structural analysis code. A postprocessor contains fracture toughness, stress-rupture, yield strength, and fatigue crack growth rate data for air-melted 1 Cr--Mo--V forgings, on the basis of which the local stress and temperature values are screened to determine the critical crack size, the initial crack size that could grow to critical size within a specified number of hours or cycles, and the minimummore » area fraction of defects that could link up to result in a significant crack. A boresonic data reduction code allows rapid sorting of indicated flaw sizes and locations to determine the regions of greatest defect density. The four separate task reports that detail the project research since January 1976 are presented. Each report is self-contained, with its own summary, contents, and references, Also available is a project summary report, which presents highlights of the research results.« less

Tubing degradation and the inspection thereof is of immediate concern in PWR steam generators. As part of a larger EPRI program, a set of three fixed-site steam generator mock-ups and an air-transportable steam generator mock-up have been designed, constructed, and demonstrated. These mock-ups are configured to accommodate a large number of tubes that contain simulated defects generally associated with each of the PWR steam generators. The immediate use of these mock-ups will be the evaluation of NDE systems for steam generator inspection from the primary-side of the tubes, particularly the evaluation of eddy-current systems. The future uses are interim evaluation of new or developmental NDE devices and systems in a realistic radiation free setting and the training of NDE personnel.

The discontinuities present in large steam turbine rotor forgings and their growth during service are of major concern since failures of these rotors are extremely expensive both in potential loss of lives and revenues. The current inservice inspections of these rotors are thus a significant part of the quality control programs of electric utilities to assure the safe and continued operation of power generating stations. The nature of the NDE processes now being used for rotor inspection and the types of internal indications which are considered technically relevant, from a stress distribution viewpoint are reviewed, and recommendations are made of where rotor examinations can be improved. In particular, the details of boresonic examination procedures are reviewed and the most probable causes of routine inspection uncertainties are identified. Minimum flaw sensitivities are described and the probabilities of detection, based on boresonic axial scan patterns are identified in terms of the measured beam profiles of typical inspection transducers. A set of acceptance criteria to be used with existing inspection systems are suggested. These criteria would require inspection service contractors to demonstrate their system's minimum sensitivity, ultimate depth and spatial resolution, and repeatability by virtue of an ability to repeatedly detect and discriminatemore » between sets of precision holes placed in specified patterns within a recommended universal calibration standard.« less