Enhanced O2 Flux of CaTi0.85Fe0.15O3−δ Based Membranes by Mn Doping

Dense symmetric membranes of CaTi_0.85?xFe_0.15Mn_xO_3?δ (x = 0.1, 0.15, 0.25, 0.4) are investigated in order to determine the optimal Mn dopant content with respect to highest O₂ flux. O₂ permeation measurements are performed as function of temperature between 700°C–1000°C and as function of the feed side ranging between 0.01 and 1 bar. X‐ray photoelectron spectroscopy is utilized to elucidate the charge state of Mn, and synchrotron radiation X‐ray powder diffraction (SR‐XPD) is employed to investigate the structure symmetry and cell volume of the perovskite phase at temperatures up to 800°C. The highest O₂ permeability is found for x = 0.25 over the whole temperature and ranges, followed by x = 0.4 above 850°C. The O₂ permeability for x = 0.25 reaches 0.01 mL(STP) min^?1 cm^?1 at 925°C with 0.21 bar feed side and Ar sweep gas. X‐ray photoelectron spectroscopy indicates that the charge state of Mn changes from approx. +3 to +4 when x > 0.1, which implies that Mn mainly improves electronic conductivity for x > 0.1. The cell volume is found to decrease linearly with Mn content, which coincides with an increase in the activation energy of O₂ permeability. These results are consistent with the interpretation of the temperature and dependency of O₂ permeation. The sintering behavior and thermal expansion properties are investigated by dilatometry, which show improved sinterability with increasing Mn content and that the thermal expansion coefficient decreases from 12.4 to 11.9 × 10^?6 K^?1 for x = 0 and x = 0.25, respectively.     

Basic Oxygen Furnace: Assessment of Recent Physicochemical Models

Metallurgical and Materials Transactions B - Modeling of the basic oxygen furnace (BOF) process, both for online monitoring and fundamental research, has gained importance in steelmaking industry...     

SUPRENUM software for the symmetric eigenvalue problem

The effecient use of the SUPRENUM computer calls for a careful choice of adequate algorithms and an implementation taking into account the special characteristics of a parallel computer with distributed memory. To demonstrate these facts, well-known algorithms solving the symmetric eigenvalue problem are presented, parallelized in particular for the SUPRENUM machine.

The main problems arise in the amount of communication calls, and ways are shown to reduce this amount by using block algorithms rather than the usual ones.     

External cost of electricity generation in Baltic States

This article deals with external cost of electricity generation in Baltic States. The costs of electricity generation and distribution are the most important criteria shaping decisions within the electricity system. However, the external cost due to air pollution should also be adequately taken into account seeking to promote new and clean technologies for electricity generation. External costs of electricity generation in the main power plants burning fossil fuel were calculated based on ExternE methodology for Baltic States during EU Framework 6 project CASES. The article presents the first results of external cost of electricity generation in Baltic States.     

Pitch Estimation by Block and Instantaneous Methods

Choosing a pitch estimation algorithm is not a simple task. One must balance between the accuracy and the reliability of the estimates. Two classes of methods are available. The first one, known as the block methods class, gives noise robust solutions and has an intrinsic averaging property, but is not very accurate, especially for the transition regions. The second one, known as the instantaneous (or event-based) methods class, gives very accurate estimates, but is considered to be inadequate in the presence of noise.In this paper, we present potential enhancements of the performance in pitch estimation, based on both block and instantaneous methods. In this respect we discuss mainly two algorithms: a nonlinear cepstral algorithm and a wavelet-based one. The first algorithm, due to the proposed nonlinear model, enhances the classical linear model performance related to the accuracy of the estimated pitch for the transition regions and to the robustness in the presence of noise. Concerning the second algorithm, to the inherent accuracy of the estimated pitch, we add robust estimates even in the presence of noise, based on the multiresolution properties of an improved wavelet transform. The obtained enhancements were evaluated on a hand-labeled speech database, and the improved algorithms are now being applied in our research concerning speech compression and prosody.     

Surveyance of disease frequency in a population by linkage to diagnostic laboratory databases. A system for monitoring the incidences of hyper- and hypothyroidism as part of the Danish iodine supplementation program

In Denmark an increase in iodine intake through salt iodization has been introduced in 1998. In parallel a program for surveyance of thyroid diseases in the population was developed as recommended by UNICEF and WHO. OBJECTIVE: To develop and evaluate a computer based system to identify and register new cases of hyper- and hypothyroidism in a well defined cohort, by linkage to diagnostic laboratory databases. DESIGN AND RESULTS: (1) Two sub cohorts for monitoring were defined (n=535,859), and evaluated to minimize loss of new cases. Collaboration was established with laboratories covering thyroid hormone analyses in the cohort; (2) a diagnostic algorithm was defined and evaluated against clinical practice; (3) evaluation of the laboratory methods employed by the four participating laboratories, to ensure they would reach the same diagnosis in a patient; (4) a register database was developed which used data imported from the laboratory databases to automatically identify previously unknown cases of hyper- and hypothyroidism and record diagnostic activity in the area. All parts of the registration were carefully evaluated. CONCLUSION: We describe for the first time a computer based system for prospective measuring the incidence rate of hyper- and hypothyroidism. The system is particularly useful for monitoring of iodine supplementation programmes.     

Exploitation or neglect.

A comparison of lengths of stay for alcoholism treatment in nonpublic and public hospitals indicates that the ratio of median stay was greater in nonpublic hospitals (2:1). While 3 explanations are possible, these results support W. R. Miller and H. K. Hester's (see record 1986-28253-001) contention that financial considerations play a dominant role in patient treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Engaging strangers in proximal interaction: Infants' social initiative.

Observed 72 infants aged 12, 18, and 24 mo in the presence of their mothers and 2 adult female strangers to assess their willingness to initiate proximal interaction (PI) with unfamiliar adults. Mothers and strangers were asked to be warmly responsive to infant overtures but not to invite interaction from the infant. A majority of the infants at the 3 ages initiated PI with one or both strangers, often repeatedly. For those who engaged in 2 or more PI bouts with the strangers, a significant upward trend in bout duration and intensity was noted. Older infants gave more toys to the strangers and initiated more mutual play. Stranger–mother distance affected amount of proximity, not PI. Mother–stranger conversation was associated with less PI with the conversing stranger. At all ages infants sought more PI with their mothers than with the strangers. Although infants initiated an appreciable amount of PI with the strangers during the 40-min observation, comparison with other studies indicates that a stranger who takes the initiative by inviting play can establish more rapport much sooner. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Statistical Models in the Study of Soil Properties

An objective study of soil properties is presented by means of statistical analysis using the least squares method. Elevation data and clay content, from six regions of an overall surveyed area, are approximated by linear and quadratic matrices. Regressions between a defined topography index of mean slopes and clay content are established. The level of significance of the relations is examined by means of computed “accounted map variability” and correlation coefficients. The results express the trend of the investigated property.