Rapid synthesis of room temperature ferromagnetic Ag-doped LaMnO3 perovskite phases by the solution combustion method

We report the rapid solution combustion synthesis and characterization of Ag-substituted LaMnO3 phases at relatively low temperature using oxalyl dihydrazide, as fuel. Structural parameters were refined by the Rietveld method using powder X-ray diffraction data. While the parent LaMnO3 crystallizes in the orthorhombic structure, the Ag-substituted compounds crystallize in the rhombohedral symmetry. On increasing Ag-content, unit cell volume and Mn-O-Mn bond angle decreases. The Fourier transform infra red spectrum shows two absorption bands corresponding to Mn-O stretching vibration (v(s) mode) and Mn-O-Mn deformation vibration (v(b) mode) around 600 cm(-1) and 400 cm(-1) for the compositions x = 0.0, 0.05 and 0.10, respectively. Electrical resistivity measurements reveal that composition-controlled metal to insulator transition, with the maximum metal to insulator being 280 K for the composition La0.75Ag0.25MnO3. Increase in magnetic moment was observed with increase in Ag-content. The maximum magnetic moment of 35 emu/g was observed for the composition La0.80Ag0.20MnO3. (C) 2010 Elsevier Ltd. All rights reserved.

Changing Paradigms in Biblical Criticism : 2 Kings 22:1 23:30 in the Flux of Discourses

The subject and methodology of biblical scholarship has expanded immense-ly during the last few decades. The traditional text-, literary-, source- and form-critical approaches, labeled historical-critical scholarship , have faced the challenge of social sciences. Various new literary, synchronic readings, sometimes characterized with the vague term postmodernism, have in turn challenged historicalcritical, and social-scientific approaches. Widened limits and diverging methodologies have caused a sense of crisis in biblical criticism. This metatheoretical thesis attempts to bridge the gap between philosophical discussion about the basis of biblical criticism and practical academic biblical scholarship. The study attempts to trace those epistemological changes that have produced the wealth of methods and results within biblical criticism. The account of the cult reform of King Josiah of Judah as reported in 2 Kings 22:1 23:30 serves as the case study because of its importance for critical study of the Hebrew Bible. Various scholarly approaches embracing 2 Kings 22:1 23:30 are experimentally arranged around four methodological positions: text, author, reader, and context. The heuristic model is a tentative application of Oliver Jahraus s model of four paradigms in literary theory. The study argues for six theses: 1) Our knowledge of the world is con-structed, fallible and theory-laden. 2) Methodological plurality is the neces-sary result of changes in epistemology and culture in general. 3) Oliver Jahraus s four methodological positions in regard to literature are also an applicable model within biblical criticism to comprehend the methodological plurality embracing the study of the Hebrew Bible. 4) Underlying the methodological discourse embracing biblical criticism is the epistemological ten-sion between the natural sciences and the humanities. 5) Biblical scholars should reconsider and analyze in detail concepts such as author and editor to overcome the dichotomy between the Göttingen and Cross schools. 6) To say something about the historicity of 2 Kings 22:1 23:30 one must bring together disparate elements from various disciplines and, finally, admit that though it may be possible to draw some permanent results, our conclusions often remain provisional.

Thermal decomposition of zirconyl oxalates I. Barium zirconyl oxalate

Conditions for the preparation of stoichiometric barium zirconyl oxalate heptahydrate (BZO) have been standardized. The thermal decomposition of BZO has been investigated employing TG, DTG and DTA techniques and chemical and gas analysis. The decomposition proceeds through four steps and is not affected much by the surrounding gas atmosphere. Both dehydration and oxalate decomposition take place in two steps. The formation of a transient intermediate containing both oxalate and carbonate groups is inferred. The decomposition of oxalate groups results in a carbonate of composition Ba2Zr2OsCO3, which decomposes between 600 and 800 ~ and yields barium zirconate. Chemical analysis, IR spectra and X-ray powder diffraction data support the identity of the intermediate as a separate entity.

Thermal decomposition of zirconyl oxalates I. Barium zirconyl oxalate

Conditions for the preparation of stoichiometric barium zirconyl oxalate heptahydrate (BZO) have been standardized. The thermal decomposition of BZO has been investigated employing TG, DTG and DTA techniques and chemical and gas analysis. The decomposition proceeds through four steps and is not affected much by the surrounding gas atmosphere. Both dehydration and oxalate decomposition take place in two steps. The formation of a transient intermediate containing both oxalate and carbonate groups is inferred. The decomposition of oxalate groups results in a carbonate of composition Ba2Zr2O5CO3, which decomposes between 600 and 800° and yields barium zirconate. Chemical analysis, IR spectra and X-ray powder diffraction data support the identity of the intermediate as a separate entity.Die Bedingungen für die Herstellung von stöchiometrischem Barium-zirconyl-oxalat Heptahydrat (BZO) wurden standardisiert. Die thermische Zersetzung von BZO wurde unter Einsatz der TG-, DTG- und DTA, sowie der chemischen und Gasanalyse untersucht. Die Zersetzung verläuft über vier Stufen und wird von der umgebenden Gasathmosphäre nicht besonders beeinflusst. Sowohl die Dehydratisierung als auch die Oxalatzersetzung erfolgt in zwei Stufen. Die Bildung einer intermediären Übergangsverbindung mit sowohl Oxalat- als auch Carbonatgruppen wirken hierbei mit. Die Zersetzung der Oxalatgruppen ergibt ein Carbonat der Zusammensetzung Ba2Zr2O5CO3, das zwischen 600 und 800° zersetzt wird und Bariumzirconat ergibt. Die Angaben der chemischen Analyse, der IR-Spekren und der Röntgen-Pulver-Diffraktion unterstützen die Identität der Intermediärverbindung als eine separate Einheit.On a standardisé les conditions de préparation de l'oxalate heptahydraté de zirconyle et de baryum (BZO) stoechiométrique. On a étudié la décomposition thermique de BZO par TG, TGD et ATD ainsi que par analyses chimiques et analyses des gaz. La décomposition a lieu en quatre étapes et n'est pas trop influencée par l'atmosphère ambiante. La déshydratation et la décomposition de l'oxalate ont lieu en deux étapes. Il se forme un composé intermédiaire de transition contenant à la fois les groupes oxalate et carbonate. La décomposition des groupes oxalate fournit un carbonate de composition Ba2Zr2O5CO3 qui se décompose entre 600 et 800° pour fournir du zirconate de baryum. L'analyse chimique, les spectres IR et la diffraction des rayons X sur poudre, apportent les preuves de l'existence d'un composé intermédiaire comme entité séparée.

Pain measurement and management in elderly patients : Clinical studies in long term hospital care and after cardiac surgery

The proportion of patients over 75 years of age, receiving all different types of healthcare, is constantly increasing. The elderly undergo surgery and anaesthetic procedures more often than middle-aged patients. Poor pain management in the elderly is still an issue. Although the elderly consumes the greatest proportion of prescribed medicines in Western Europe, most clinical pharmacological studies have been performed in healthy volunteers or middle-aged patients. The aim of this study was to investigate pain measurement and management in cognitively impaired patients in long term hospital care and in cognitively normal elderly patients after cardiac surgery. This thesis incorporated 366 patients, including 86 home-dwelling or hospitalized elderly with chronic pain and 280 patients undergoing cardiac surgery with acute pain. The mean age of patients was 77 (SD ± 8) years and approximately 8400 pain measurements were performed with four pain scales: Verbal Rating Scale (VRS), the Visual Analogue Scale (VAS), the Red Wedge Scale (RWS), and the Facial Pain Scale (FPS). Cognitive function, depression, functional ability in daily life, postoperative sedation and postoperative confusion were assessed with MMSE, GDS, Barthel Index, RASS, and CAM-ICU, respectively. The effects and plasma concentrations of fentanyl and oxycodone were measured in elderly (≥ 75 years) and middle-aged patients (≤ 60 years) and the opioid-sparing effect of pregabalin was studied after cardiac surgery. The VRS pain scores after movement correlated with the Barthel Index. The VRS was most successful in the groups of demented patients (MMSE 17-23, 11-16 and ≤ 10) and in elderly patients on the first day after cardiac surgery. The elderly had a higher plasma concentration of fentanyl at the end of surgery than younger patients. The plasma concentrations of oxycodone were comparable between the groups. Pain intensity on the VRS was lower and the sedation scores were higher in the elderly. Total oxycodone consumption during five postoperative days was reduced by 48% and the CAM-ICU scores were higher on the first postoperative day in the pregabalin group. The incidence of postoperative pain during movement was lower in the pregabalin group three months after surgery. This investigation demonstrates that chronic pain did not seem to impair daily activities in home-dwelling Finnish elderly. The VRS appeared to be applicable for elderly patients with clear cognitive dysfunction (MMSE ≤17) and it was the most feasible pain scale for the early postoperative period after cardiac surgery. After cardiac surgery, plasma concentrations of fentanyl in elderly were elevated, although oxycodone concentrations were at similar level compared to middle-aged patients. The elderly had less pain and were more sedated after doses of oxycodone. Therefore, particular attention must be given to individual dosing of the opioids in elderly surgical patients, who often need a smaller amount for adequate analgesia than middle-aged patients. The administration of pregabalin reduced postoperative oxycodone consumption after cardiac surgery. Pregabalin-treated patients had less confusion, and additionally to less postoperative pain on the first postoperative day and during movement at three months post-surgery. Pregabalin might be a new alternative as analgesic for acute postoperative and chronic pain management in the elderly. Its clinical role and safety remains to be verified in large-scale randomized and controlled studies. In the future, many clinical trials in the older category of patients will be needed to facilitate improvements in health care methods.

Computational Fluid Dynamics in Combustion

Computational fluid dynamics has reached a stage where flow field in practical situation can be predicted to aid the design and to probe into the fundamental flow physics to understand and resolve the issues in fundamental fluid mechanics The study examines the computation of reacting flows After exploring the conservation equations for species and energy, the methods of closing the reaction rate terms in turbulent flow have been examined briefly Two cases of computation where combustion-flow interaction plays important role, have been discussed to illustrate the computational aspects and the physical insight that can be gained by the reacting flow computation

Finlandssvenska åsikter om och attityder till modern språkpåverkan

The study describes and analyzes Finland Swedes attitudes to modern-day linguistic influence, the relationship between informants explicitly reported views and the implicit attitudes they express towards language influence. The methods are primarily sociolinguistic. For the analysis of opinions and attitudes I have further developed and tested a new tool in attitude research. With statistical correlation analysis of data collected through a quantitative survey I describe the views that Swedish-language Finns (N=500) report on the influence of English, on imports, and on domain loss. With experimental matchedguise techniques, I study Finland-Swedes (N=600) subconscious reactions to English imports in spoken text. My results show that the subconscious reactions in some respects differ markedly from the views informants explicitly report that they have: informants respond that they would like English words that come into Swedish to be replaced by Swedish replacement words, but in a matched-guise test on their subconscious attitudes, the informants consider English words in a Swedish context to have a positive effect. The topic is further dealt with in interviews where I examine 36 informants implicit attitudes through interactional sociolinguistic analyses. This study comes close to pragmatic discourse analysis in its focus on pragmatic particles and modality. The study makes a rather strict distinction between explicitly expressed opinions and implicit, subconscious attitudes. The quantitative analyses suggest that the opinions we express can be tied to the explicit in language. The outcome of the matched-guise test shows that it is furthermore possible to find subconscious, implicit attitudes that people in actual situations rely on when they make decisions. The discourse analysis finds many subconscious signals, but it also shows that the signals arise in interaction with one s interlocutor, the situation, and the norms in the society. To account for this I have introduced the concept of socioconscious attitude. Socioconscious attitudes reflect not only the traditions and values the utterer grew up with, but also the speaker s relation to the social situation (s)he takes part in.

A new approach to the kinetics of size reduction in ball milling

The rate of breakage of feed in ball milling is usually represented in the form of a first-order rate equation. The equation was developed by treating a simple batch test mill as a well mixed reactor. Several case of deviation from the rule have been reported in the literature. This is attributed to the fact that accumulated fines interfere with the feed material and breaking events are masked by these fines. In the present paper, a new rate equation is proposed which takes into account the retarding effect of fines during milling. For this purpose the analogy of diffusion of ions through permeable membranes is adopted, with suitable modifications. The validity of the model is cross checked with the data obtained in batch grinding of ?850/+600 ?m size quartz. The proposed equation enables calculation of the rate of breakage of the feed at any instant of time.

Bioleaching of sulphides under applied potentials

The influence of applied DC potentials on the activity and growth of Thiobacillus ferrooxidans, as well as on the dissolution behaviour of some base metal sulphides is discussed with reference to bioleaching. Selective bioleaching of zinc from sphalerite could be achieved under an applied potential of −500 mV (saturated calomel electrode) from binary mineral mixtures containing the zinc mineral and chalcopyrite or pyrite. On the other hand, bioleaching of pyrite and chalcopyrite was found to be enhanced under positive potentials of +400 mV and +600 mV, respectively. Probable mechanisms in the electrobioleaching of sulphides are examined with respect to galvanic, microbiological and applied potential effects.

A delta13C record of late Quaternary climate change from tropical peats in southern India

STABLE-ISOTOPE ratios of carbon in soils or lake sediments1-3 and of oxygen and hydrogen in peats4,5 have been found to reflect past moisture variations and hence to provide valuable palaeoclimate records. Previous applications of the technique to peat have been restricted to temperate regions, largely because tropical climate variations are less pronounced, making them harder to resolve. Here we present a deltaC-13 record spanning the past 20 kyr from peats in the Nilgiri hills, southern India. Because the site is at high altitude (>2,000 m above sea level), it is possible to resolve a clear climate signal. We observe the key climate shifts that are already known to have occurred during the last glacial maximum (18 kyr ago) and the subsequent deglaciation. In addition, we observe an arid phase from 6 to 3.5 kyr ago, and a short, wet phase about 600 years ago. The latter appears to correspond to the Mediaeval Warm Period, which previously was believed to be confined to Europe and North America6,7. Our results therefore suggest that this event may have extended over the entire Northern Hemisphere.

Effect of Substrate and Annealing Temperatures on Mechanical Properties of Ti-rich NiTi Films

The effect of substrate and annealing temperatures on mechanical properties of Ti-rich NiTi films deposited on Si (100) substrates by DC magnetron sputtering was studied by nanoindentation. NiTi films were deposited at two substrate temperatures viz. 300 and 400 degrees C. NiTi films deposited at 300 degrees C were annealed for 4 h at four different temperatures, i.e. 300, 400, 500 and 600 degrees C whereas films deposited at 400 degrees C were annealed for 4 h at three different temperatures, i.e. 400, 500 and 600 degrees C. The elastic modulus and hardness of the films were found to be the same in the as-deposited as well as annealed conditions for both substrate temperatures. For a given substrate temperature, the hardness and elastic modulus were found to remain unchanged as long as the films were amorphous. However, both elastic modulus and hardness showed an increase with increasing annealing temperature as the films become crystalline. The results were explained on the basis of the change in microstructure of the film with change in annealing temperature.

Influence of cast versus wrought microstructure on the processing map for hot working of stainless steel type AISI 304

Processing maps for hot working of as-cast and wrought stainless steels of type AISI 304 have been developed in the temperature range 600 to 1250°C and strain rate range 0.001 to 100 s−1. The domain of dynamic recrystallization (DRX) in as-cast material occurs at higher temperatures (1250°C) and lower strain rates (0.001 s−1) than in the wrought steel (1100°C and 0.01 s−1). The effect is explained in terms of enhanced nucleation rate of DRX due to the carbide, ferrite particles, stable oxides/nitrides and second-phase intermetallics in the as-cast microstructure. The DRX domain is wider in the wrought material although the peak efficiency is less (32%) than in the as-cast case (40%). The flow instability regime is not significantly affected by the initial microstructure

Processing map for hot working of stainless steel type AISI 316L

Processing and instability maps using a dynamic materials model have been developed for stainless steel type AISI 316L in the temperature range 600-1250-degrees-C and strain rate range 0.001-100 s-1 with a view to optimising its hot workability. Stainless steel type AISI 316L undergoes dynamic recrystallisation, with a peak efficiency of 35% at 1250-degrees-C and 0.05 s-1, which are the optimum parameters for hot working this material. The material undergoes dynamic recovery at 900-degrees-C and 0.001 s-1. The increase in the dynamic recrystallisation and dynamic recovery temperatures in comparison with stainless steel type AISI 304L is attributed to the presence of a backstress caused by the molybdenum additions. These results are in general agreement with those reported elsewhere on stainless steel type 316 deformed in hot extrusion and hot torsion. At temperatures < 850-degrees-C and strain rates > 10 s-1, the material exhibits flow localisation owing to adiabatic shear band formation, whereas at higher temperatures (> 850-degrees-C) and strain rates (> 10 s-1) mechanical twinning and wavy slip bands are observed. (C) 1993 The Institute of Materials.

Processing maps for hot working of Cu-Ni-Zn alloys Part II Alpha-Beta nickel silver

The constitutive behaviour of agr-beta nickel silver in the temperature range 600�850 °C and strainrate range 0.001�100s�1 was characterized with the help of a processing map generated on the principles of the dynamic materials model. On the basis of the flow-stress data, processing maps showing the variation of the efficiency of power dissipation (given by [2m/(m+1)], wherem is the strain-rate sensitivity) with temperature and strain rate were obtained, agr-beta nickel silver exhibits a single domain at temperatures greater than 700 °C and at strain rates lower than 1 s�1 with a maximum efficiency of power dissipation of about 42% occurring at about 850 °C and at 0.1 s�1. In the domain, the agr phase undergoes dynamic recrystallization and controls the deformation of the alloy, while the beta phase deforms superplastically. Optimum conditions for the processing of agr-beta nickel silver are 850 °C and 0.1 s�1. The material undergoes unstable flow at strain rates of 10 and 100 s�1 and in the temperature range 600�750 °C, manifestated in the form of adiabatic shear bands.