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Desulfurization phenomenon of Ni-base superalloy using a solid CaO was identified by adjusting the temperature of melt. Ni-base superalloy and NiS powder were heated together at 1400 °C, 1500 °C, and 1600 °C. Dense and porous CaO rods were inserted into the melts individually. After the rods were pulled out, CaO, CaS, and calcium aluminates were detected on the rods by X-ray diffraction analysis. Electron probe microanalysis showed that only Ca, O, Al, and S distributed at the melt/CaO interfaces. At 1500 °C and 1600 °C, Al and S were also detected at particle boundaries in the rods. S contents in the alloys decreased as the desulfurization time passed and the temperature was raised. There was no prominent correlation between the rod porosity and the S contents. The desulfurization reaction was suggested to be that CaO, Al, and S react to generate CaS and calcium aluminates. When the temperature is high enough, the calcium aluminates form a solid–liquid coexisting state. Effective diffusion coefficient, which shows the S diffusivity in the generated layer at the melt/CaO interface, depends on the temperature and can be expressed by the Arrhenius equation. It has been supposed that the desulfurization reaction mainly occurs on CaO, and a macroscale surface area controls the desulfurization rate.

Introduction: We have developed the Dementia Elderly Odayaka Scale (DEOS) to evaluate psychosocial aspects in older people. The DEOS can be used to assess well-being, such as personhood and social interaction. Objective: The aim of this study was to apply the 18-item DEOS in participants with dementia and to examine the characteristics and usefulness of this scale. Methods: Facility staff provided care for the participants while taking into consideration each participant’s individuality and strong points. The DEOS was applied at the beginning of the interventions and at 1 and 2 months after the start of the interventions. The changes in the participants’ behaviors and their DEOS scores were then evaluated over time. Results: We examined 13 participants (2 men, 11 women) between the ages of 68 and 91 years. In 60% of the participants the DEOS score increased over time. When care interventions were tailored toward communication and leadership for the 2 men, according to each of their individualities, we observed increases in their scores for “social interaction” at 1 and 2 months thereafter. We also observed increases in the scores for “Expression of emotions” category in 2 of the 5 cases who received an aromatherapy massage. Discussion/Conclusion: The changes in the scores over time and the contents of the field notes were consistent with each other, suggesting that the DEOS can be used both to evaluate the effects of interventions and to plan care that takes advantage of each participant’s positive aspects.

This paper proposes a method for alloy composition screening using the creep property of a single crystal (SC) for designing new Ni-base powder metallurgy (P/M) turbine disc superalloys. A commercial Ni-base disc alloy, U720Li®, a Ni-Co-base disc alloy, TMW-4M3, and a Ni-base conventionally cast alloy, TM-47, were selected for investigation. Their SC and P/M samples were prepared such that their γ/γ′ structures were similar. Moreover, tensile creep tests were performed on SC samples, and compressive creep tests were performed on SC and P/M samples. The tensile creep test results of SC samples at 1073 K (800 °C) and 735 MPa indicate that 0.2 and 1 pct creep times, as well as rupture life, are long in the order of TM-47 SC, TMW-4M3 SC, and U720Li SC. These results simulate the intragranular creep resistances of the corresponding P/M alloys. Furthermore, there is no significant difference in 0.2 and 1 pct compressive creep times between the SC and P/M samples of each alloy. Additionally, the 0.2 and 1 pct creep times of tensile and compressive creep tests of every alloy had an identical order. Therefore, alloy composition screening using SC creep property enables the design of new disc alloys with excellent creep resistance.

Purpose The forced oscillation technique (FOT) is a non-invasive method to measure respiratory impedance, the respiratory resistance (Rrs) and reactance (Xrs). The disease probability measure (DPM) is a useful computed tomography (CT) imaging variable for the assessment of gas trapping and emphysema in patients with chronic obstructive pulmonary disease (COPD) using pairs of inspiratory and expiratory CT images. We aimed to develop FOT-based phenotypes and determine whether the phenotypes and their imaging characteristics could facilitate the understanding of COPD pathophysiology. Patients and methods FOT and spirometry were examined in 164 COPD patients and 22 non-COPD smokers. COPD patients were divided into four FOT-based phenotypes (NL, normal group; RD, resistance-dominant group; XD, reactance-dominant group; and MIX, mixed group) based on the 3rd quartile values of R5 (Rrs at 5Hz) and X5 (Xrs at 5Hz) in the non-COPD group. The emphysematous lesions and the airway lesions were quantitatively assessed in CT images by low attenuation volume and the square root of the wall area of a hypothetical airway with an internal perimeter of 10 mm (√Aaw at Pi10), respectively. DPM imaging analysis was also performed in 131 COPD patients. We investigated the differences in COPD parameters between the FOT-based phenotypes. Results √Aaw at Pi10 were significantly higher in the RD, XD, and MIX groups than in the NL group. The XD group showed lower pulmonary function and higher dyspnea scores than the RD group. No significant changes in DPM values were observed between the RD and the NL groups. The gas-trapping area was significantly higher in the XD group than in the NL group. The MIX group showed the highest dyspnea score, most emphysematous lesions, and the lowest forced expiratory volume in 1 s % predicted value. Conclusion The FOT-based phenotyping may be useful to assess pathophysiological changes of COPD with CT assessments.

The constraint values of dose-volume histogram (DVH) parameters for radiation pneumonitis (RP) prediction have not been uniform in previous studies. We compared the differences between conventional DVH parameters and DVH parameters with high attenuation volume (HAV) in CT imaging in both esophageal cancer and lung cancer patients to determine the most suitable DVH parameters in predicting RP onset. Seventy-seven and 72 patients who underwent radiation therapy for lung cancer and esophageal cancer, respectively, were retrospectively assessed. RP was valued according to the Common Terminology Criteria for Adverse Events. We quantified HAV with quantitative computed tomography analysis. We compared conventional DVH parameters and DVH parameters with HAV in both groups of patients. Then, the thresholds of DVH parameters that predicted symptomatic RP and the differences in threshold of DVH parameters between lung cancer and esophageal cancer patient groups were compared. The predictive performance of DVH parameters for symptomatic RP was compared using the area under the receiver operating characteristic curve. Mean lung dose, HAV30% (the proportion of the lung with HAV receiving ≥30 Gy), and HAV20% were the top three parameters in lung cancer, while HAV10%, HAV5%, and V10 (the percentage of lung volume receiving 10 Gy or more) were the top three in esophageal cancer. By comparing the differences in the threshold for parameters predicting RP between the two cancers, we saw that HAV30% retained the same value in both cancers. DVH parameters with HAV showed narrow differences in the threshold between the two cancer patient groups compared to conventional DVH parameters. DVH parameters with HAV may have higher commonality than conventional DVH parameters in both patient groups tested.

The direct and complete recycling method for Ni-base superalloy is being developed and studied to reduce the material cost for cost-effective operation of gas turbine systems. Understanding the effect of sulfur contamination is important to determine allowable sulfur content after the recycling. However, in the case of single-crystal superalloys, this effect on material properties is not well known except for the detrimental effect on the oxidation resistance. In the present study, creep tests, aging tests, and cyclic oxidation tests have been performed on PWA1484 with varying sulfur content. The increasing sulfur content has been found to correlate with degradation of properties evaluated here. It is observed that the decrease in creep life in PWA1484 due to sulfur doping is primarily due to coarsening of the γ/γ′ interfacial dislocation network, increase in precipitation kinetics of topologically closed-packed phase, and decrease in oxidation resistance. For recycling purposes, a CaO crucible was used in the casting process, which successfully decreased the sulfur level in the alloy, and the resulting material showed comparable or even better properties in comparison to the low sulfur content material.

Strength of Ni-base single-crystal superalloys under high temperature and low stress creep usually is enhanced by formation of γ/γ′ raft structure and larger aspect ratio of γ′ phase in the γ/γ′ raft structure. Elastic misfit between γ and γ′ phases is one of the most important factors to control the aspect ratio of the γ′ phase in the γ/γ′ raft structure formed under external stress. The aspect ratio of the γ′ phase is controlled by kinetics for the γ/γ′ raft structure formation, which is affected by a strain inhomogeneity caused by this elastic misfit between the γ and γ′ phases under external stress. To realize a new alloy design approach to control the aspect ratio of the γ′ phase in the γ/γ′ raft structure, this research aimed to obtain the regression equations which can predict elastic modulus of the individual γ and γ′ phases for multi-component Ni-base single-crystal superalloys based on measurements of elastic modulus of Ni-base single-crystal alloys. Elastic modulus of the individual γ and γ′ phases of various kinds of Ni-base single-crystal alloys was measured by using rectangular parallelepiped resonance (RPR) method. Using the analyzed and referenced elastic modulus, regression equations for predicting longitudinal elastic modulus of the individual γ and γ′ phases and its temperature and composition dependence were obtained. Detailed analysis of the elastic modulus and its composition dependence was executed to clarify the contribution of each element on the elastic modulus. At 900 °C, Re, Ta, Ti, Al, and Mo reduce the longitudinal elastic modulus in the γ phase. On the other hand, Ru, Re, Ta, Ti, Al, W, and Mo enlarge the elastic modulus in the γ′ phase.

In order to investigate the applicability of a direct and complete recycling method to commercial-scale ingot production, 3 tons of a Ni-base single crystal (SC) superalloy, TMS-1700(MGA1700) was melted and desulfurized by CaO during the melting. Sulfur content in the molten alloy was reduced from about 23 ppm to about 2 ppm within 60 min after adding granular CaO to the molten alloy. Microstructural observations using SEM and EPMA showed no presence of inclusions caused by CaO addition. Creep rupture lives of the recycle-simulated TMS-1700 were equivalent to that of the standard TMS-1700 under the conditions from 800 °C/735 MPa to 1100 °C/137 MPa. The recycle-simulated TMS-1700 exhibits even better oxidation resistance compared with the standard TMS-1700, which has better oxidation resistance than CMSX-4TM. Thus, it became clear that the CaO desulfurization improves the oxidation resistance of Ni-base superalloys. High cycle fatigue (HCF) properties of the standard and the recycle-simulated TMS-1700 were equivalent. From the results described above, it has been suggested that the application of direct and complete recycling method to commercial-scale ingot production is feasible.

International audience; An advanced Ni-base single-crystal superalloy, TMS-238, has the highest temperature capability, but there is still potential to improve its high-temperature properties. In the present study, aiming for that further improvement, TMS-238 was melted in a CaO crucible, which replaced an Al2O3 crucible. Creep tests at 1100 °C/137 MPa and cyclic oxidation tests at 1100 °C were conducted to compare the high-temperature properties of TMS-238 melted in an Al2O3vs a CaO crucible. Regardless of the melting crucible, the creep properties of the samples were equivalent. Meanwhile, TMS-238 melted in a CaO crucible exhibited better oxidation resistance. Although the composition of the oxide scale was almost the same, the sample melted in an Al2O3 crucible had its oxide scale spalled, while a continuous oxide scale was formed on the sample melted in a CaO crucible. Dissolved Ca capturing S as CaS and preventing segregation of S at the metal-oxide interface is a possible reason for the improvement of the oxide scale adhesiveness. The results indicated that melting in a CaO crucible can improve the oxidation resistance of the original superalloys while maintaining their creep properties.

Introduction: Eosinophilic airway inflammation is now recognized as one of the important pathophysiology of chronic obstructive pulmonary disease (COPD). Objectives: To investigate the usability of fractional exhaled nitric oxide (FeNO) as a maker of eosinophilic inflammation compared with other biomarkers like blood eosinophil counts and serum IgE level in stable COPD patients. Patients and methods: A total of 146 stable COPD patients were enrolled from the outpatient clinic of respiratory medicine in our hospital from May 2011 to June 2016. The patients underwent spirometry and chest CT. FeNO was measured before spirometry. Peripheral blood eosinophil counts and serum IgE level were also measured. Using chest CT data, emphysematous lesions and the airway wall thickness were assessed by the percentage of low attenuation voxels (LAV%) and by the square root of airway wall area of the hypothetical airway with an internal perimeter of 10 mm (√Aaw at Pi10), respectively. Results: The participants were 10 females and 136 males with a mean age of 71.8 ± 7.3 (mean ± SD) years old. FEV1 %predicted was 68.5 ± 21.2% and FeNO was 29 ± 20 ppb. Laboratory findings showed that blood eosinophils were 237.0 ± 181.1/μL, and median serum IgE was 121.4 IU/ml (IQR, 27.9 - 439.3 IU/ml). FeNO was positively correlated with serum IgE (p=0.003), but not correlated with blood eosinophils (p=0.064). Serum IgE and blood eosinophils were positively correlated with each other (p=0.03). FeNO was not correlated with CT measured markers such as LAV% and √Aaw at Pi10. Conclusions: FeNO can be an easy, noninvasive and useful marker of eosinophilic airway inflammation in stable COPD patients.

Background: In out-patient clinics, having simple procedures to check for signs of dementia is invaluable. In the present study, we evaluated the imitation of hand gestures to detect visuomotor deficits in dementia in clinical practice. Methods: In all, 1219 subjects were enrolled in the present study, including 497 with Alzheimer's disease (AD), 98 with dementia with Lewy bodies (DLB), 71 with other types of dementia diseases, 175 with a Clinical Dementia Rating (CDR) of 0.5, and 378 normal controls. All subjects were aged 65 years or older. Subjects were recruited from 10 clinics and two communities. Visuomotor function was evaluated by the Yamaguchi fox–pigeon imitation test (YFPIT), which consists of a simple one-handed sign for ‘fox’ and a complex two-handed sign for ‘pigeon’, a rapid, game-like test with low psychological burden. Results: The success rate (successful/total) for imitating the ‘pigeon’ hand gesture was reduced as the severity of the dementia increased: 85.7% in normal controls, 60.6% in CDR 0.5 (mild cognitive impairment), 39.2% in CDR 1 (mild dementia), 21.2% in CDR 2 (moderate dementia), and 5.7% in CDR 3 (severe dementia). The success rate for imitating the ‘pigeon’ hand gesture was higher in patients with DLB than AD within the CDR 1 group (51.2% vs 35.4%, respectively), but lower for patients with DLB than AD within the CDR 2 group (12.5% vs 24.4%, respectively). The success of imitating the hand gesture for ‘fox’ was similar for patients with AD and DLB. Of those subjects who failed to imitate the hand gesture for ‘pigeon’, 49.5% of those with AD showed the palm–palm pattern (both palms facing outward), suggesting deficits of perspective conversion from the first-person to the third-person. Conversely, 52.8% of patients with DLB showed a dorsum–dorsum pattern (both dorsa facing outwards), suggesting deterioration of visual attention and recognition. Conclusion: In conclusion, the YFPIT is a useful test to detect visuomotor deficits in dementia that can differentiate between AD and DLB.

Background and objective: COPD is one of the leading causes of morbidity and mortality worldwide, and its prevalence continues to increase. Although spirometry is indispensable for the diagnosis of COPD, other simple and reliable tools are necessary for screening of COPD because spirometry is not widely available. This study investigated the usefulness of a combination of an electronic FEV1/FEV6 meter (PiKo-6) with a COPD questionnaire as a screening method in patients with cardiovascular diseases. Methods: The PiKo-6 and the COPD questionnaire of the International Primary Care Airways Group were used to screen patients attending a cardiovascular outpatient clinic. Patients with FEV1/FEV6

Current use of TBCs is subjected to premature spallation failure mainly due to the formation of thermally grown oxides (TGOs). Although extensive research has been carried out to gain better understanding of the thermo - mechanical and -chemical characteristics of TBCs, laboratory-scale studies and simulation tests are often carried out in conditions significantly differed from the complex and extreme environment typically of a modern gas-turbine engine, thus, failed to truly model service conditions. In particular, the difference in oxygen partial pressure and the effects of contaminants present in the engine compartment have often been neglected. In this respect, an investigation is carried out to study the in-service degradation of an EB-PVD TBC coated nozzle-guide vane. Several modes of degradation were observed due to three factors: 1) presence of residual stresses induced by the thermal-expansion mismatches, 2) evolution of bond coat microstructure and subsequent formation of oxide spinels, 3) deposition of CMAS on the surface of TBC.

A calculation of the interface energy for the Ni-Al binary alloy, including the inter-phase boundary (IPB) energy and the anti-phase boundary (APB) energy, has been performed using the Cluster Variation Method (CVM) with the tetrahedron approximation within the temperature range of 600°C~1300°C. The calculated IPB energies range between 8 and 13 mJ/m2, while the APB energies range between 24 and 46 mJ/m2. Additionally, the dependence of the average composition and the order parameter on distance with the compositionally diffuse interfacial regions has been computed. The calculation also shows the width of the diffuse IPB increases with the temperature linearly.

The effects of Ru additions on the microstructure and phase stability of the Ni-base superalloy U720LI were examined. The results show that the alloys with Ru contents of 0 to 6 wt pct had a dendritic structure, and the volume fraction of the primary γ solid-solution phase in the dendritic core increased with the increase in the Ru content. The Ru additions to U720LI had little effect on suppressing the formation of the σ phase, because the elemental partitioning of Cr, Mo, and Co in the γ solid-solution phase was not influenced by the Ru additions. However, the coarsening of the γ′ phase was restrained by the Ru additions in the U720LI.

This paper presents the effects of the cross-sectional in-plane crystal orientation (θ) on the structural strength of single crystal turbine vanes using the finite element method (FEM). The material of the turbine vanes is the single crystal superalloy TMS-75. The obtained results show that the elastic constant matrix (c'44) changes were by above 60% due to the orientation variation (0° < θ < 90°). The dependency of the structural strength of the turbine vane on the crystal orientation was calculated using von Mises stress equation. The strength of the turbine vane was strongly related to θ, and also related to the model shape and load. This influence becomes more significant near the leading edge of the turbine vane where it is most likely to fracture.

Advanced high-temperature strengths in Ni-base single crystal (SC) superalloys have been achieved through the addition of Re in small amounts. However, Re has a strong tendency to form topologically close-packed (TCP) phases that decrease the creep strength, thus, increasing the Re content has undesirable consequences. This effect of Re addition is controlled in 4th generation superalloys where the formation of TCP phases is avoided by the addition of platinum-group metals (PGMs) such as Ru and Ir, and increased creep strengths have been achieved. Furthermore, PGM elements and solution strengthening elements including Re have been added in 5th generation superalloys to achieve superior high temperature strength. However, because Re is an expensive element and longer homogenization time is required for high-Re alloys, the use of this alloying element results in higher material and production cost, and lower productivity. In this paper, a new type of Ni-base single crystal superalloy is proposed. This alloy does not contain Re but still reaches the high temperature capabilities of 4th and 5th generation superalloys, and has the advantages of low material cost and easy heat treatment. 1st generation single crystal superalloys do not contain Re, therefore, these are suitable material to be used as the master alloy for this alloy development. TMS-26, which was developed through High Temperature Materials 21 Project, NIMS, was used as the master alloy and, by the addition of Mo and Ru, a new single crystal superalloy TMS-174 was developed. Mo has the effect of controlling the lattice misfit and solid solution strengthening. Mo also promotes TCP formation, however this is avoided by the addition of Ru. The creep rupture life of TMS-174 at 900°C and 392 MPa was slightly shorter than that of TMS-138, which is a conventional 4th generation single-crystal superalloy with 5 mass%Ru. However, at 1100°C and 137 MPa, creep rupture life of TMS-174 was found to be 18% longer compared to TMS-138. This new alloy development strategy of adding solid solution strengthening elements and PGM elements to form non-Re containing superalloys was demonstrated to be successful. This strategy has the potential for superior alloy developments in the future because of the benefits of cost reduction and attainable material properties that are comparable to 4th and 5th generation superalloys.

Our Ni-base single crystal (SC) superalloys that have been designated as 4th and 5th generation SC alloys contain Ru for the enhancement of microstructure stability. The authors have previously reported that Ir addition was as effective as Ru for enhancing the microstructure stability. In this paper, Ir was added to TMS-173, a new 5th generation SC alloy, by substituting out Ru. The creep strength of this new SC alloy, designated as TMS-173(Ir), was then compared to that of the original Ru-containing alloys, TMS-173. Creep tests were conducted for these SC superalloys under several conditions: 800°C/735 MPa, 900°C/392 MPa, 1000°C/245 MPa and 1100°C/137 MPa. The Ir-containing alloys showed shorter creep rupture life than The Ru-containing one in higher temperature and lower stress conditions such as 1100°C/137 MPa. However, at lower temperature and higher stress conditions, The Ir-containing alloy showed longer creep rupture life than Ru-containing one; the former showed 3.2 times longer creep rupture life than the latter in the creep tests at 900°C/392 MPa. Microstructure observations of creep-ruptured specimens confirmed that Ir was as effective as Ru for microstructure stability.

The Pebble Bed Modular Reactor (PBMR) is a small atomic power reactor which can be used in areas where the electric power transmission network is not well developed. It generates electricity by gas-turbines that used He-gas as a coolant. Ni-based superalloys are the primary materials used in gas-turbines. However if conventional Ni-base superalloys are to be used for PBMR, turbine maintenances will be difficult due to Co, as it can produce {sup 60}Co a recitative material that possesses a long half-life. Therefore, Co-free Ni-base superalloys are required for PBMR. In this paper, a Co-free single-crystal (SC) superalloy, TMS-82+ (-Co), was developed; it was the same chemical composition as the 2nd generation SC superalloy, TMS-82+, except that it is Co-free creep tests were performed on the developed alloy, TMS-82+, under three condition; 900degC/392 MPa, 1000degC/245 MPa, and 1100degC/137 MPa; CMSX-4, a popular SC alloy, was used as comparison. TMS-82+ (-Co) displayed superior creep-rupture life in all creep tests; however, detrimental TCP were observed in the microstructure of the sample that underwent creep testing at 1100degC/137 MPa. This, the developed Co-free SC alloy should be further modified for long-term microstructural stability. Elimination of phase formation will allow the alloy to be utilized in the PBMR. (author)

Internal elastic strain, and its change accompanied with the raft formation during creep deformation in the Ni-based single crystal superalloy (TMS-26) have been investigated by X-ray diffractometry. The elastic strain caused by the lattice misfit between g and g' phases has markedly been changed by creep deformation especially in the directions perpendicular to the [001] tensile axis. The change in the elastic strain can be explained by the effect of creep dislocations stacked at g/g' interfaces. The evolution of the elastic stress field estimated from the elastic strain has explained well the transition from primary creep stage to the second one.

In the ‘High Temperature Materials 21’ project, fourth generation single crystal (SC) superalloys have been developed adding Ru as a phase stabilizing element. A relationship between the amount of TCP-phase and the creep strength has been investigated for a series of Ni-base SC superalloys with 2 to 5 mass% Ru; these alloys were designed using an SC superalloy containing 5 mass% Re as a base alloy. The amount of TCP-phase decreased with increased Ru content from 2 to 5 mass%. and the amount of γ′ envelope, which normally forms on the TCP plate, decrease also with increase in Ru content. The creep strength increase with these structual changes but the main reason was considered to be the decrease in volume fraction of the γ′ envelope rather than the decrease in the amount of TCP-phase.

High strength single crystal (SC) superalloys for jet-engines and gas turbines have been developed in the “High Temperature Materials 21” project. In the context of this project, the authors previously developed the world strongest superalloy TMS-162 using an alloy TMS-138 as a base and adding Mo as a strengthening element as well as Ru as a phase stabilizing element. In the present study, Ta, Nb and Re were examined as possible strengthening elements instead of Mo. Ru was also added to stabilize the microstructure. Creep tests of the SC samples showed that Re had a similar effect as Mo for strengthening the SC superalloy, whereas the effects of Ta and Nb additions were not so significant as those of Re and Mo. These were attributed to the effects of the elements on the lattice misfit; Re and Mo are known to be partitioned preferentially to the γ phase rather than to the γ′ phase so that the aγ-aγ′ misfit increases. This is considered to be the reason for the excellent creep strength of the sample with the Re addition.

Ni-base directionally solidified (DS) superalloys have an advantage of production costs over single crystal (SC) superalloys because of better yield rate of casting and simpler heat treatment compared with SC superalloys. In this study, we designed a 4th generation DS superalloy, TMD-111, based on our 5th generation SC superalloy, TMS-162, containing 5 mass%Ru; we added C and B on TMS-162 to strengthen the grain boundaries. The alloy was directionally solidified and heat treated under four different conditions, i.e., as cast, as solution treated, solution treated and aged, and solution treated and two step aged. The solution treated and two step aged sample showed the highest creep strength, although the effect of heat treatment was found to be relatively small. All the samples except for as cast ones showed longer 1% creep strain under a 1100°C/137 MPa compared with that of CMSX-10, a typical third generation SC superalloy.

The partitioning behavior of platinum group metals (PGMs) on the γ and γ′ phases of Ni-base superalloys has been investigated with alloys containing 5 mass% Re and 1 at.% PGMs. It was shown that Ru partitions preferably into the γ, while Rh, Pd, and Pt partition into the γ′, and Ir partitions almost equally. The partitioning behavior is not affected by the 1 at.% PGM addition.

The elastic constants of the rafted Ni-base single-crystal superalloy, TMS-26, at high temperatures (~1000 °C) have been studied with acoustic resonance methods. The rafted superalloy can be regarded as an elastic body of tetragonal symmetry. The elastic anisotropy factors, c11/c33 and E 1 0 0 /E 0 0 1 , increase with temperature up to 1.010–1.025. Although a micromechanics model can reproduce this trend, the calculated anisotropy (~1.001) is much smaller than the measurements, which can be related with the internal strain due to the lattice misfit. The elastic anisotropy of E 0 0 1 1 0 0 =E 0 1 0 contributes to the transverse rafting under external stress.

Rafting mechanism in Ni-base single-crystal superalloys has been discussed with the total mechanical energy calculated for typical microstructures. We found that the actual rafting phenomena cannot be explained within the coherent elastic regime. The present calculations reveal that (i) only the transverse rafted structure with laminates normal to the stress direction can be realized, regardless of tensile or compressive stresses, and (ii) the lattice misfit is not relevant to the choice of the rafted structures. However, when the eigenstrain of the spherical (dilatational) symmetry changes into that of the tetragonal symmetry with misfit dislocations on the γ/γ′ interfaces, the signs of lattice misfit and external stress govern the choice of the transverse or longitudinal rafts. It is concluded that the rafting belongs to an elastic–plastic phenomenon.

A 29-year-old woman with primary myelofibrosis developed severe pneumonia, and 20 days later her 31-year-old sister also contracted pneumonia. The first patient had been in contact with parakeets but the second patient had not been in contact with any birds. Psittacosis was diagnosed in both cases by microplate immunofluorescence antibody technique. Person-to-person transmission between the sisters was suspected to have taken place.

A 21-year-old man presented persistent dry cough, general malaise, loss of appetite, decreased sexual desire and double vision. Chest radiograph revealed a mass shadow in the left upper lobe. Histopathological diagnosis of the tumor was squamous cell carcinoma. Brain computed tomography and magnetic resonance imaging revealed a metastasis to the pituitary gland. Hypopituitarism was diagnosed by pituitary function tests. Diabetes insipidus was absent and the function of the posterior lobe of the pituitary gland was preserved. Hypopituitarism due to pituitary metastasis is a rare complication of lung cancer, and has never been reported in a patient as young as 21 years old.

The effects of oxygen supply conditions and specific biofilm interfacial area on the phenol removal rate in a three-phase fluidized bed bioreactor were evaluated. The experimental data were well-explained by the semi-theoretical equation based on the assumption that the reaction rate follows first-order reaction kinetics with respect to oxygen and zero-order one with respect to phenol. Two cases, biological reaction as rate-controlling step and oxygen absorption as rate-controlling step, were both explicable by this semi-theoretical equation. The maximum volumetric phenol removal rate was 27.4 kg·m−3·d−1. On a evalue les effets des conditions d'apport en oxygene et de la surface interfaciale specifique du biofilm sur la vitesse de retrait du phenol dans un bioreacteur a lit fluidise triphasique. Les donnees experimentales sont bien expliquees par l'equation semi-theorique reposant sur l'hypothese que la vitesse de reaction obeit a une cinetique de reaction du premier ordre pour l'oxygene et d'ordre zero pour le phenol. Deux cas, soient la reaction biologique comme etape de regulation de la vitesse et l'absorption d'oxygene comme etape de regulation de la vitesse, sont explicables par cette equation semi-theorique. La vitesse volumetrique maximale de retrait du phenol est de 27,4 kg·m−3·d−1.

Study objective To compare the etiology of community-acquired pneumonia in Japan and Western countries, the causative pathogens were prospectively investigated in patients requiring hospitalization. Design Prospective study over a 3-year period. Setting A community general hospital in Japan. Patients Three hundred twenty-six episodes of community-acquired pneumonia in 318 patients admitted to the hospital between July 1994 and June 1997. Methods The microbiological diagnosis was based on the results of quantitative sputum culture, blood culture, and other invasive procedures, including transthoracic needle aspiration or bronchoscopic examination. Serologic tests for Mycoplasma pneumoniae , Chlamydia spp, Legionella spp, and viruses were also routinely performed. Results Causative pathogens were identified in 199 episodes (61%). Streptococcus pneumoniae was the most common pathogen (23%), followed by Haemophilus influenzae (7.4%), M pneumoniae (4.9%), and Klebsiella pneumoniae (4.3%). The Streptococcus milleri group and Chlamydia pneumoniae were detected in 3.7 and 3.4% of the episodes, respectively. Pneumonia due to Legionella spp was recognized in only two patients. Conclusions The etiology of community-acquired pneumonia in Japan did not differ markedly when compared with that of Western countries except for the low incidence of Legionella pneumonia. C pneumoniae and the S milleri group, which are emerging or newly recognized pathogens, were also significant causative microorganisms.

Mesoscopic structures of SiC fibers produced from polycarbosilane by different methods were studied by diffraction and small-angle scattering of neutrons and x-rays. Microvoids of a size of 4–10 Å in diameter have been observed for the first time by neutron scattering in a medium momentum transfer range (Q = 0.1–1.0 Å−1). The size and the volume fraction of β–SiC particles were determined for fibers prepared at different heat-treatment temperatures. The results show that wide-angle neutron scattering measurements are especially useful for the study of the mesoscopic structure of multicomponent materials.