bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Aspects of Borate Chemistry under High-Pressure
Authors: Huppertz Hubert 
Published: February 2009

AbstractAt the moment, over 1100 borate crystal structures are listed in the Inorganic Crystal Structure Database ICSD. High-pressure investigations in this field are rare and were mainly performed from a geological point of view. Starting in 1999, systematic high-pressure / high-temperature experiments up to maximum pressures of 16 GPa have been carried out, using the multianvil technique to explore the synthetic possibilities in the field of borates under extreme conditions. This approach led to a variety of interesting new materials, which are unattainableviaconventional solid state syntheses. The communication will give a short survey of the most important results in the last years.
Driving Electrons to Anti-Bonding States: On the Synthesis of New Niobium Cluster Chlorides by Electrochemical Lithium Intercalation
Authors: Garcia-Alvarado Flaviano , Kuhn Alois , Gonzalo Elena , Meyer H. Juergen 
Published: February 2009

AbstractThe lithium intercalation chemistry of LiNb6Cl15, a 16 e− Nb-cluster, has been explored in order to obtain new Nb-cluster compounds. As a result, three different phases have been detected. Full de-intercalation of lithium produces Nb6Cl15, a new 15 e− Nb-cluster. The oxidation reaction is reversible since lithium can be intercalated again to produce the parent LiNb6Cl15. On the other hand, intercalation of lithium into LiNb6Cl15 seems to proceed through two single phases with the following stoichiometries: Li1.5Nb6Cl15 and Li3Nb6Cl15. For these two compositions the extra electrons (0.5 and 2 respectively/formula) should enter the eg* molecular orbitals arising from Nb-Nb interactions inside the cluster. The reductions of LiNb6Cl15 leading to these two new electron-rich Nb-cluster are reversible as detected by chronopotentiometry.
Electronic Structure, Magnetism and Spin-Fluctuations in Fe-As Based Superconductors
Authors: Singh David Joseph , Du Mao-Hua , Zhang Lijun , Subedi Alaska , An Jiming 
Published: February 2009

AbstractThe physical properties of the layered iron superconductors and related phases are discussed starting from first principles calculations. The electronic structure is described as that of metallic Fe2+ square lattice sheets with substantial direct Fe-Fe hopping and interactions with the neighboring anionic pnictogens or chalcogens. The materials have a semi-metallic band structure, and in particular the Fermi surface consists of small cylindrical electron sections centered at the zone corner, and compensating hole sections at the zone boundary. The density of states N(EF) is high placing the materials near itinerant magnetism in general, and furthermore the small Fermi surface sections are well nested leading to a tendency towards a spin density wave. Comparison of experimental and density functional results imply the presence of exceptionally strong spin fluctuations in these materials. Superconductivity is discussed within this context.
A Study of [Cr-O6]-based rutile analogues by means of EELS
Authors: Arevalo-Lopez Angel M. , Castillo-Martinez Elizabeth , Alario-Franco Miguel Ángel 
Published: February 2009

AbstractWe present in here the study by means of electron energy loss spectroscopy (EELS) of several rutile based oxides, having in common the presence of octahedrally oxygen coordinated chromium, [Cr-O6], in three different formal oxidation states: Cr4+ in CrO2, a regular rutile; Cr3+ in CrOOH, a H bonded orthorrombic distorted rutile and in CrTaO4, a metal disordered rutile and Cr2+ in CrTa2O6 an ordered trirutile structure. A linear relationship is observed between the formal oxidation state of chromium in all these rutile oxides and the separation between the Cr-L2,3 and O-K energy loss peaks.
Single-Crystal Thin Films of SrFeO2 and LaNiO2 with Infinite-Layer Structures
Authors: Shimakawa Yuichi , Inoue Satoru , Kawai Masanori , Ichikawa Noriya , Mizumaki Masaichiro , Kawamura Naomi 
Published: February 2009

AbstractInfinite-layer-structure epitaxial thin films of SrFeO2 and LaNiO2 respectively were prepared by low-temperature reduction with CaH2 from brownmillerite SrFeO2.5 and perovskite LaNiO3 epitaxial thin films grown on single-crystal substrates. The reduction process, removing oxygen ions from the perovskite-structure framework and causing rearrangements of oxygen ions, topotactically transforms the initial compounds to the c-axis oriented infinite-layer-structure epitaxial thin films. Consequently, the oxidation state of transition-metal ions in the film changed in wide ranges.
Single Step Synthesis of Y2O3:Eu3+ Nanophosphor Prepared by Flame Spray Pyrolysis
Authors: Lee Jae Seok , Kim Sejin , Oh Myoung Hwan , Ranade Madhav B , Singh Rajiv K 
Published: February 2009

AbstractA novel ceramic synthesis technique, flame spray pyrolysis (FSP) was investigated for the production of nanophosphor particles. Among the various types of synthesis technique for phosphors, FSP is a powerful method which is capable of producing particles with good crystallinity and high luminescence efficiency. Red light emitting Eu3+ doped Y2O3 nanophosphor was prepared by FSP from nitrate based liquid precursors with high flame temperature. Flame temperature is an important factor to obtain phosphor particles with dense and spherical shape. Different molar percentage of urea was added into the precursor, addition of urea increases the temperature in the flame zone and promotes the formation of nano-size and spherical shaped particles. The importance of urea in the precursor to obtain well dispersed Y2O3:Eu3+ nanophosphor has been studied. The characteristics of nanophosphor such as crystallinity, morphology and photoluminescence in the presence of different moles of urea in nitrate based aqueous solution were investigated. On varying the overall concentration of the precursor, both the optical properties and crystallinity were investigated. XRD spectra showed as-prepared phosphors were obtained directly as cubic phase Y2O3:Eu3+ nanophosphor with high crystallinity and without any post-heat treatments. Luminescence intensity of nanophosphor increased with the amount of urea till 2 M percentages, further increase in urea concentration was found to reduce the PL intensity. We have developed a continuous single-step fabrication method for nanocrystalline Y2O3:Eu3+ nanophosphor without any post-heat treatments procedure.
Organically-functionalised supertetrahedra as building blocks for hybrid materials
Authors: Vaqueiro Paz , Romero M Lucia 
Published: February 2009

AbstractThe crystal structures of gallium sulfides prepared under solvothermal conditions, using 4-picoline as a solvent, are described. These materials contain [Ga10S16(NC6H7)4]2− clusters, in which the terminal S2− anions have been replaced by covalently bonded 4-picoline molecules. Whilst these phases contain isolated supertetrahedral clusters separated by organic moieties, linkage of such clusters via organic ligands is possible under suitable reaction conditions. These organically-functionalised supertetrahedra could therefore be used to design novel Metal-Organic frameworks (MOFs) in which the normally-encountered metal centers are replaced by supertetrahedral clusters.
Mixed Valent Rhodates
Authors: Mizoguch Hiroshi , Sleight Arthur William , Subramanian Mas 
Published: February 2009

AbstractExploratory synthesis of mixed oxides of rhodium has produced many new rhodates containing both Rh3+ and Rh4+. The structures of all the compounds are based on networks formed from RhO6 octahedra sharing both corners and edges. All compounds exhibit good electrical conductivity, and some also show a high thermopower.
Crystallization Processes of Amorphous Si During Excimer Laser Annealing in Complete-melting and Near-complete-Melting Conditions: A Molecular Dynamics Study
Authors: Ogata Tomohiko , Mitani Takanori , Munetoh Shinji , Motooka Teruaki 
Published: February 2009

AbstractWe investigated crystallization processes of amorphous Si (a-Si) during the excimer laser annealing in the complete-melting and near-complete-melting conditions by using molecular dynamics simulations. The initial a-Si configuration was prepared by quenching liquid Si (l-Si) in a MD cell with a size of 50×50×150Å3 composed of 18666 atoms. KrF excimer laser (wavelength: 248nm) annealing processes of a-Si were calculated by taking account of the change in the optical constant upon melting during a laser pulse shot with the intensity Ioexp[−(t–t0)2/ς2] (Io: laser fluence, t: irradiation time). The refractive indices of a-Si and l-Si were set at n+ik=1.0+3.0i and n+ik=1.8+3.0i, respectively. The simulated results well reproduced the observed melting rate and the near-complete-melting and complete-melting conditions were obtained for Io = 160mJ/cm2 and 180mJ/cm2, respectively. It was found that larger grains were obtained in the near-complete-melting condition. Our MD simulations also suggest that nucleation occurs first in a-Si and subsequent crystallization proceeds toward l-Si in the near-complete-melting case.
Pre-edge peak of Ti K XANES: Determined by Short- or Medium-Range Structure?
Authors: Jiang Nan 
Published: February 2009

ABSTRACTThe calculations of Ti K-edge X-ray absorption near-edge structures (XANES) in fresnoite Sr2TiSi2O8 are carried out using multiple-scattering method. The origins of the pre-edge peak along with the fine structures in the main peak of Ti K-edge XANES are interpreted by comparing the calculations in various modified structure models. It concludes that the pre-edge peak is dominantly determined by the structure (including both coordination and bond lengths) within the nearest-neighbor distance, while the fine structures beyond the pre-edge peak region are sensitively determined by the structure extending to the medium-range distance
Ascending Auctions with Package Bidding
Authors: Ausubel Lawrence M , Milgrom Paul R 
Published: February 2009

Abstract
A family of ascending package auction models is introduced in which bidders may determine their own packages on which to bid. In the proxy auction (revelation game) versions, the outcome is a point in the core of the exchange economy for the reported preferences. When payoffs are linear in money and goods are substitutes, sincere reporting constitutes a Nash equilibrium and the outcome coincides with the Vickrey auction outcome. Even when goods are not substitutes, ascending proxy auction equilibria lie in the core with respect to the true preferences. Compared to the Vickrey auction, the proxy auctions generate higher equilibrium revenues, are less vulnerable to shill bidding and collusion, can handle budget constraints much more robustly, and may provide better ex ante investment incentives.
Orbicular granite near Jelenia Góra in southwestern Poland: the first outcrops?
Authors: Kennan Pádhraig , Lorenc Marek 
Published: February 2009

Orbicular granite near Jelenia Góra in southwestern Poland: the first outcrops?In 1802, Leopold von Buch described some outcrops of orbicular granite in the Karkonosze granite, Lower Silesia, Poland. In that publication, Abraham Gottlieb Werner wrote a foreword dated 1800. The Silesian discovery predates that of the well-known orbicular diorite (Napoleonite) in outcrop on Corsica and, thus, may be the first ever record of this distinctive rock type in its geological context. The characterizing, closely-packed, simple orbs comprise K-feldspar cores surrounded by rims of radiating K-feldspar and quartz. Rapid growth from a hydrous, pegmatitic melt is indicated. The Karkonosze outcrop, in the timing of its discovery, is a unique part of the geological heritage.
Understanding the Professional Socialization of Canadian Physical Therapy Students: A Qualitative Investigation
Authors: Bartlett Doreen J. , Deborah Lucy S. , Bisbee Leslie , Conti-Becker Angela 
Published: February 2009

Purpose: To understand the professional socialization of physical therapy (PT) students. Method: Forty-two students enrolled in our newly developed master's degree programme wrote three-page reflective journals on a critical learning incident after each of three selected clinical experiences. The journals were coded and analyzed, and major themes were identified and described. A separate cohort of 44 students participated in focus groups after the same three clinical experiences to check the trustworthiness of the results. Results: Following the first placement, the main themes coded were emotions, self-confidence, professionalism in the real world, communication, and learning by doing. After the intermediate placement, major themes were idealism versus realism, depth of communication with clients, and breadth of communication with family members and colleagues. Aspects of clinical learning were variable, and self-confidence remained an issue. After the final placement, most students were deeply engaged with their clients and self-confidence had developed to the point of self-efficacy. Tensions increased between the concept of ideal practice and the pragmatics of actual practice, and the concept of self as protégé (rather than as object of the supervisor's evaluation) emerged. The themes were subsequently assembled in a booklet with representative quotations. Conclusion: These results contribute to foundational knowledge required by PT educators, including clinical instructors, by explicitly describing the professional socialization of PT students.
Management of Fall-Related Injuries in the Elderly: A Retrospective Chart Review of Patients Presenting to the Emergency Department of a Community-Based Teaching Hospital
Authors: Miller Erin , Wightman Elizabeth , Rumbolt Karla , McConnell Sara , Berg Katherine , Devereaux Moira , Campbell Fiona 
Published: February 2009

Purpose: To identify current practice for elderly individuals who have sustained a fall-related injury and subsequently presented to the emergency department (ED) of a community-based hospital in Toronto, Ontario. Methods: A retrospective longitudinal chart review was conducted for 300 persons, 65 years of age and older, who presented to the ED of a community-based teaching hospital with a fall from June 2004 through May 2005. Data were collected using a tool created by the investigators (based on information gathered through a literature review) to capture information related to risk factors for falling. Results: Our study sample was demographically similar to elderly individuals in other fall-related studies. Most patients discharged directly from the ED did not receive multidisciplinary care. In the ED, all patients saw a nurse or physician, while only 1.3% (n = 4) saw a physical therapist, 3.0% (n = 9) saw an occupational therapist, and 5.3% (n = 16) saw a social worker. At discharge, 62% (n = 152) had no documented referral for follow-up care. Abilities related to falls in elderly individuals were not consistently assessed in the ED. Frequency of assessment for these abilities was as follows: (1) gait, 10.2%; (2) balance, 4.1%; (3) lower-extremity range of motion, 4.9%; (4) lower-extremity strength, 2.0%; (5) cognition, 26.1%; (6) vision, 2.0%; (7) ability to perform activities of daily living, 7.3%. In the 6 months following the index fall, 8.3% of patients returned to the ED of the same hospital because of a subsequent fall. Conclusions: In the ED, fall-related risk factors were not consistently assessed or documented, and few patients received multidisciplinary management. Since elderly individuals who fall commonly present to the ED, the implementation of evidence-based strategies aimed at preventing repeat falls should be considered.
Relationship between Preoperative Patient Characteristics and Expectations in Candidates for Total Knee Arthroplasty
Authors: Razmjou Helen , Finkelstein Joel A. , Yee Albert , Holtby Richard , Vidmar Marjan , Ford Michael 
Published: February 2009

Purpose: The purpose of this study was to determine the relationship between patient expectations for improvement following primary total knee arthroplasty (TKA) and patient preoperative characteristics. Methods: This was a cross-sectional analysis of preoperative expectations. Expectations for improvement were evaluated in six distinct domains. The baseline factors used as independent variables were age, gender, presence of comorbidity, sub-domains of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC; pain, stiffness, physical limitation related to lower extremity), and SF-36 physical and mental health component scores. Stepwise logistic regression analysis was applied to examine the relationships between dependent and independent variables. Results: The study cohort consisted of 236 candidates for TKA (154 women and 82 men, mean age 67, SD = 9.98). Expectations were high on average. Presence of comorbidity was associated with expectations of pain relief. Preoperative mental health was related to expectations for a return to activities of daily living; age, gender, physical health, and mental health were related to expectations for improved leisure, recreational, and sports activities. Preoperative physical health was related to expectations for potential return to full recovery. No baseline factors were associated with expectations for improved range of motion or for providing care to and interacting with others. Conclusion: Expectations related to recovery from surgery appeared to have distinct dimensions and were associated with patient baseline characteristics.
Prediction of thermodynamic activities in binary iron-based alloys using two-point Padé approximants
Authors: Stella Eduardo , Stella Jorge 
Published: February 2009

AbstractA method for predicting activities as a function of the concentration in liquid solutions for binary FeCo, FeCu, FeNi, FeMn and FePd systems using Padé approximants is presented. Padé approximants of orders 4/0 and 1/3 are proposed for the model using as input variables only the conditions from Henry's law at a given temperature. Results derived from the approximant 4/0 show good agreement with the experimental data in systems with moderate positive and negative deviations from the Raoultian behaviour. On the other hand, the approximant 1/3 shows a satisfactory agreement in the FeCu system which exhibits a high positive deviation from the Raoultian behaviour. A comparison with the results from a Redlich – Kister expansion using the same input conditions is discussed.
Determination of the concentration dependent diffusion coefficient of nitrogen in expanded austenite
Authors: Christiansen Thomas L. , Somers Marcel A. J. 
Published: February 2009

AbstractThe concentration dependent diffusion coefficient of nitrogen in expanded austenite was determined from the rate of retracting nitrogen from thin initially N-saturated coupons. Nitrogen saturated homogeneous foils of expanded austenite were obtained by nitriding AISI 304 and AISI 316 in pure ammonia at 693 K and 718 K. Denitriding experiments were performed by equilibrating the foils with a successively lower nitrogen activity, as imposed by a gas mixture of ammonia and hydrogen. The concentration depen-dent diffusion coefficient of nitrogen in expanded austenite was approximated in the composition range where nitrogen can be extracted by hydrogen gas at the diffusion temperature. Numerical simulation of the denitriding experiments shows that the thus determined concentration dependent diffusion coefficients are an accurate approximation of the actual diffusivity of nitrogen in expanded austenite.
Deformation and fracture of Ti-base nanostructured composite
Authors: Das Jayanta , Buem Kim Ki , Zhang Zhe-Feng , He Guo , Müller Clemens , Eckert Jürgen 
Published: February 2009

Abstract
The in-situ formation of nano-eutectic/primary dendrite bulk composites in Ti-base multicomponent alloy systems allows the design of advanced high strength materials, where a nanostructured matrix is combined with ductile β-Ti solid solution dendrites as a toughening phase. This microstructure can be achieved over a wide range of cooling rates. The multicomponent recipe stabilizes the β-Ti phase and helps to reduce the eutectic spacing to the nanometer scale. The superiority in the mechanical properties, i. e. high room temperature ductility (up to 30 %) as well as high strength (up to 2600 MPa), stems from the possibility to tailor the alloy composition leading to the formation of different volume fractions of dendrites in a nanostructured eutectic matrix. All composites with high volume fraction of dendrites offer a high ductility (∊p = 8 – 30 %) and a final failure angle in the range of 46 – 51°. The role of the volume fraction of the dendrites in the composite in enhancing the ductility as well as the fracture angle is critically assessed. The deformation and fracture mechanisms are linked to the macroscopic fracture features as well as to impingement of the shear bands leading to rotation of the shear plane and lattice distortion at the atomic level.
X-ray analysis of steep residual stress gradients: The 2θ-derivative method
Authors: Erbacher Thomas , Wanner Alexander 
Published: February 2009

Abstract
Machined ceramics and other hard materials exhibit very steep subsurface gradients of residual stresses. X-ray analysis enables the non-destructive assessment of the distributions of these residual stresses versus the distance from the surface via variation of the penetration depth of the X-rays. Conventional evaluation procedures are based on continuous or piecewise defined polynomial functions of stress versus distance, which are fitted to the X-ray data by means of complex solution schemes. These solution schemes are, however, in many cases unstable and difficult to handle. We have developed an entirely novel evaluation procedure which is based on polynomials fitted to the “2θ vs. sin2 ψ” plots obtained from the X-ray measurements. It is shown that the residual stress profiles can be computed explicitly from these polynomials without any further assumptions. The evaluation procedure is described in detail and demonstrated in a case study on ground alumina ceramics.
Unconstrained solidification and characterisation of near-eutectic Al–Cu–Ag alloys
Authors: Ebzeeva S. , Nagels E. , Froyen L. 
Published: February 2009

AbstractThis study focuses on the microstructure formation in two Al – Cu – Ag alloys with near-eutectic composition on either side of the α(Al)/θ-Al2Cu groove. The alloys solidified equiaxially with two different cooling rates for each composition of alloy. The primary phases formed are α(Al) or θ-Al2Cu, but univariant and invariant eutectic reactions are common. In hypoeutectic samples macrosegregation of the α(Al) phase occurred. The univariant α(Al)/θ-Al2Cu eutectic in these samples is formed by coupled two-phase structures. The univariant eutectic in the samples, which exhibit primary θ-Al2Cu, grew partially competitively due to the α(Al) single phase instability.It is suggested that the difference in solubility of the segregating element Ag in α(Al) and θ-Al2Cu phases and processing parameters such as cooling rates determine the resulting microstructure.
Microstructural control of FeB-inoculated mottled low-alloy white iron by a design of experiments approach
Authors: Asensio Juan , Álvarez José F. , Vander Voort George F. 
Published: February 2009

Abstract
The present research identifies manufacturing factors that influence the metastable constituent in mottled Nihard cast irons. These irons constitute the roll shells of duplex work rolls processed by centrifugal casting. The research methodology employed a saturated design of experiments program with 7 factors, 8 experiments and a resolution of III. An increase from 6 to 10 kg/T of inoculated FeB enhanced metastable solidification by increasing the amount of ledeburite and the amount of cementite. Similarly, decreasing the Si content from 1.1 – 1.2 to 0.9 – 1.0 wt.% increased the amount of ledeburite and cementite. Finally, the use of casting machines without isolating sleeves increased the roll barrel hardness in the as-cast condition and after tempering.