bluuebunny/crossref_metadata_2025 huggingface dataset:
Critical success factors for modernising public financial management information systems in Bosnia and Herzegovina
Authors: Vickland Scott , Nieuwenhuijs Inez
Published: April 2005

This article identifies a number of critical factors that have contributed to the successful implementation of a public financial management information system in the Republic of Bosnia and Herzegovina (BiH). The information system, funded by USAID and implemented by Emerging Markets Group from 1999 to 2004, has revolutionised accounting practices and has contributed to a more transparent and effective public sector. This article describes the project's context and purpose, its main features, challenges and obstacles. It continues by outlining the critical success factors that have contributed to the success of the project in a challenging environment. The project was implemented in a rather unique environment since it was initiated not long after the end of the civil war and the creation of the Republic of BiH. The Republic of BiH inherited the former socialist Yugoslavian payment systems. There were no adequate public financial management systems in place, and the project team could essentially start from scratch. The project team designed and implemented an accrual accounting system, and unlike the situation in many countries, relieved the government from having to transform their financial management system from cash‐based accounting to accrual accounting. Copyright © 2005 John Wiley & Sons, Ltd.
Learning from the Philippine occupation: nation‐building and institutional development in Iraq and other high security risk nations
Authors: Klingner Donald E. , Jones L. R.
Published: April 2005

Outcomes of armed conflict in Afghanistan and Iraq indicate that the U.S. has been unprepared to fully address problems related to establishing social and economic stability, security and governance in the aftermath of war. This is unfortunate, given that U.S. policy makers' nation‐building efforts to achieve stability, security and good governance in these nations do not reflect what they should already have learnt about organisational and institutional development from past experiences providing significant development assistance to highly unstable nations. Based on the analysis rendered in this article, ‘smart practice’ development administration in such nations comprises the following key points that link nation building to institutional/organisational development:

Nation building (creating new national sovereignty) is different from, and harder than, building government capacity (creating or strengthening institutions and organisations).

Given that building government capacity typically requires years of patient assistance and financing, it is better to build on existing indigenous institutions like the civil service and military.

The time and expense of development assistance to high security risk nations means that it is advisable to establish a multi‐lateral development assistance plan and a multi‐national, multi‐institutional framework for financing development to pay for all that is necessary over a long period of time (i.e. 20–50 years).

Policy makers should emphasise social stability and stable economic growth under self‐governance to prevent actual or perceived economic exploitation.

Policy makers' diplomatic efforts should secure accommodation of various stakeholders sufficient to permit compromise leading to formation of an independent government.

Where occupation appears necessary to achieve security and stability, policy makers should allocate enough troops and money to do the job, and accurately assess and report all costs of military occupation and nation building.

Once occupation has occurred, policy makers should not withdraw military support in a way that would increase the likelihood of civil war.

Premature withdrawal of security, economic and political support prior to the point where high security risk nations are capable of governing themselves will cause a power vacuum, and may result in fragmented regional leadership by warlords. Copyright © 2005 John Wiley & Sons, Ltd.
Sol–gel process of alkoxysilanes in an elastomer medium
Authors: Pietrasik Joanna , Zaborski Marian
Published: April 2005

The influence of different mixtures of di‐, tri‐ and tetraalkoxysilanes on the synthesis and character of silica filler particles prepared by a sol–gel reaction in an elastomer medium was investigated. Silica fillers containing organic substituents with basic properties were synthesized in acrylonitrile–butadiene rubber, with and without carboxyl groups, as well as in decane as a suspension medium, which was treated as an elastomer model. 29Si NMR spectroscopy and scanning electron microscopy (SEM) were used to determine the structure of the resulting silica fillers, and their dispersion in the elastomeric medium. Water, alcohol or other polar solvents were not used in the process of creating the silica fillers as it is impossible to introduce them into the elastomer. Copyright © 2005 Society of Chemical Industry
SHORT COMMUNICATION: ACCELERATED PUBLICATION: Dye solar cells without electrolyte or hole‐transport layers: a feasibility study of a concept based on direct regeneration of the dye by metallic conductors
Authors: Lenzmann F. O. , O'Regan B. C. , Smits J. J. T. , Kuipers H. P. C. E. , Sommeling P. M. , Slooff L. H. , van Roosmalen J. A. M.
Published: April 2005

Flat structures consisting of dense dye‐sensitized TiO2 films with various materials for dye regeneration (TiO2/dye/regeneration material) are compared. Au and PEDOT:PSS were tested as metal or metal‐like regeneration materials and compared with reference compounds, such as the redox couple I−/I in solution and p‐type CuSCN. Under the exclusion of TiO2 bandgap excitation, the short‐circuit photocurrent densities for the various structures differ by less than ∼30%, suggesting comparable charge separation efficiencies. The good performance of a metallic regeneration material implies, that the frequently assumed requirement of p‐type or ‘hole conducting’ properties for the regeneration material in solid state dye solar cells is questionable. Copyright © 2005 John Wiley & Sons, Ltd.
Correlation of a resistance‐associated Rdl mutation in the German cockroach, Blattella germanica (L), with persistent dieldrin resistance in two Danish field populations
Authors: Hansen Kenneth Klingenberg , Kristensen Michael , Jensen Karl‐Martin Vagn
Published: April 2005

Danish Blattella germanica (L) populations carry the resistance‐associated mutation A302S within the Resistance to dieldrin (Rdl) gene. The mutation has remained in field populations long after the discontinuation of dieldrin for cockroach control. The mutation has also persisted in our laboratory strains with high and intermediate frequencies for more than 8 years without selection. The toxicity of dieldrin was tested by topical application to male cockroaches in the susceptible strain DPIL‐SUS and two field strains, Zo960302 and Su960304, which were 1270‐ and 15‐fold resistant to dieldrin at LD50. We report the sequencing of exon 7 of the B germanica Rdl gene and the finding of the putative resistance‐associated A302S mutation. We have developed and implemented a PCR‐based diagnostic method with the detection of a restriction endonuclease polymorphism, which allows for easy discrimination of susceptible, resistant and heterozygote genotypes. The frequency of the resistance‐associate allele A302S was 0.97 and 0.38 in the Zo960302 and Su960304 populations, respectively. The cockroach Rdl A302S allele confers high dieldrin resistance in homozygotes and intermediate resistance in heterozygotes, and its presence is responsible for the persisting dieldrin resistance in Danish populations of B germanica. Copyright © 2005 Society of Chemical Industry
Hall conductivity as a topological invariant
Authors: Kunold A. , Torres M.
Published: April 2005

The object of the present work is to study the quantum Hall effect through its symmetries and topological aspects. We consider the model of an electron moving in a two‐dimensional lattice in the presence of applied in‐plain electric field and perpendicular magnetic field. We refer to this as the two dimensional electric–magnetic Bloch problem (EMB). The Hall conductivity quantization beyond the linear response approximation is analyzed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin and charge polarization in quantum dot arrays
Authors: Rojas F. , Cota E. , Mireles F. , Ulloa S. E.
Published: April 2005

The role of spin and charge distribution in a planar semiconductor quantum dot array (square geometry) with two electrons is studied in the presence of a driver cell and magnetic nanoparticles located near two quantum dots providing a local magnetic field. We use an extended Hubbard model to describe the electrons in the cell, taking into account intra and intercell Coulomb interaction, intracell tunneling, Rashba spin‐orbit interaction while hopping, as well as the local magnetic interaction with the magnetic nanoparticles. We find that under physically suitable conditions, controlled by the driver, spin and charge cell polarization (spin‐switching effect) can be attained, which is fully tunable by an electrical mechanism. This effect can be useful for spintronics and/or quantum computation applications. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Selective Polymer‐Assisted Product Sequestration for the Generation of Combinatorial Libraries of 1,3‐Thiazines
Authors: Strohmeier Gernot A. , Reidlinger Claudia , Kappe C. Oliver
Published: April 2005

Combinatorial approaches for the solution‐phase synthesis of diverse 1,3‐thiazine‐5‐carboxylate libraries are described. Knoevenagel condensation of β‐ketoesters and aldehydes utilizing a polymer‐supported catalyst furnished the anticipated enones, which were subsequently reacted with thioureas to generate 1,3‐thiazine heterocycles among various by‐products. In the key step, the 1,3‐thiazines were selectively sequestered by a polymer‐bound sulfonic acid. Subsequent base‐induced release from the polymer (catch and release) produced 24 1,3‐thiazine products in yields up to 79%, good to excellent purities and in high diversity. In contrast to the polymer‐bound acid‐mediated reaction, this method tolerates more complex building blocks. Furthermore, polymer‐assisted methods for N2‐derivatization were performed, including reactions with activated carboxylic acids, sulfonyl chlorides and isocyanates.
Photodissociation tandem mass spectrometry at 266 nm of an aliphatic peptide derivatized with phenyl isothiocyanate and 4‐sulfophenyl isothiocyanate
Authors: Oh Joo Yeon , Moon Jeong Hee , Lee Yong Ho , Hyung Seok‐Won , Lee Sang‐Won , Kim Myung Soo
Published: April 2005

Photodissociation (PD) tandem mass spectra have been obtained at 266 nm for the protonated molecules of a tryptic peptide, ASHLGLAR, and of its phenyl isothiocyanate and 4‐sulfophenyl isothiocyanate derivatives, generated by matrix‐assisted laser desorption/ionization. Derivatization with the aromatic chromophores greatly reduced the intensity of the laser required for efficient PD. Major fragment ions observed in the three spectra are quite similar. General features of the PD tandem mass spectra and their potential utility for analytical purposes are discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Hydrogen Bonds in Potassium Amide‐Ammonia(1/2), KNH2·2NH3
Authors: Kraus Florian , Korber Nikolaus
Published: April 2005

Potassium amide‐ammonia(1/2), KNH2·2NH3 (1) was obtained as a side product in the reaction of distilled potassium with dicesium‐dodecahydro‐closo‐dodecaborate Cs2B12H12 in liquid ammonia at −38 °C. The compound crystallises in the orthorhombic space group C2221 with Z = 4, a = 6.8386(7) Å, b = 9.9525(10) Å, c = 6.5903(6) Å and V = 448.54(8) Å3 as column shaped colorless crystals. The compound contains one‐dimensional infinite potassium‐amide‐ammonia‐strands parallel to the crystallographic c‐axis which are interconnected by interstrand N–H···N‐hydrogen bonds.
Zur Kristallchemie der Oxoiridate
Authors: Müller‐Buschbaum Hanskarl
Published: April 2005

Das Review faßt die Kristallchemie der Oxoiridate zusammen. Der überwiegende Teil aller Oxoiridate zeigt Iridium in einer oktaedrischen Umgebung. Unter diesem Aspekt wird die Kristallchemie der Oxoiridate, ausgehend von zueinander isolierten IrO6‐Oktaedern, über Polyedertripel, zu IrO6‐Oktaederketten und IrO6‐Oktaedernetzen geordnet. Iridium ist Bestandteil in Polyederketten der sogenannten „eindimensionalen Oxide”︁, der Perowskite und der K2NiF4‐Struktur. Es bildet Varianten der Ruddlesden‐Popper‐Phasen und ist Bestandteil gestapelter Ir2O9‐Oktaederdoppel und Ir3O12‐Oktaedertripel. Glanzlichter der Oxoiridate sind die metallreichen Alkalimetall‐Oxoiridate, die Iridium in planaren IrO4‐Polygonen aufweisen. Es ist schließlich bemerkenswert, daß Ir6+ durch die Perowskitstruktur stabilisiert wird.
Cd(H2O)2[C6H3(COO)2(COOH)] ‐ Ein zweidimensionales Koordinationspolymer mit Kationenaustauschermerkmalen
Authors: Köferstein Roberto , Robl Christian
Published: April 2005

Cd(H2O)2[C6H3(COO)2(COOH)] ‐ A Two‐Dimensional Coordination Polymer with Cationexchanger Features

Monoclinic single crystals of Cd(H2O)2[C6H3(COO)2(COOH)] have been prepared in aqueous solution at 80 °C. Space group C2/c (no. 15), a = 1973.0(2), b = 910.74(7), c = 1336.81(10) pm, β = 117.897(8)°, V = 2.1230(3) nm3, Z = 8. Cd2+ is coordinated in a moderately distorted pentagonal bipyramidal fashion by five oxygen atoms stemming from the monohydrogentrimesinate anions in the equatorial plane and two water molecules in the apical positions (Cd–O 224.0(2) – 255.0(2) pm). The connection of Cd2+ with [C6H3(COO)2(COOH)]2− yields a two‐dimensional coordination polymer. The atoms of the monohydrogentrimesinate anion form in good approximation a common plane. Thermogravimetric analysis in air shows that the dehydrated compound is stable up to 390 °C. Further decomposition yields CdO.
Synthese, Kristallstruktur und spektroskopische Untersuchungen von Ba5(BO3)3CN
Authors: Schmid Sabine , Schnick Wolfgang
Published: April 2005

Synthesis, Crystal Structure, and Spectroscopic Investigations of Ba5(BO3)3CN

Barium borate cyanide Ba5(BO3)3CN was synthesized at 1450 °C as coarsely crystalline colorless to pale yellow crystals by the reaction of BaCO3 with BN, barium and tungsten in tungsten crucibles using a radiofrequency furnace. The structure was solved by single‐crystal X‐ray diffractometry (Ba5(BO3)3CN, Z = 4, C2221, a = 1045.3(2), b = 1479.6(3), c = 798.9(2) pm, R1 = 0.0240, 1847 independent reflections, 91 refined parameters). Besides Ba2+ there are trigonal BO33− ions (B‐O 137 – 140 pm) and CN− ions (C‐N 114(2) pm). The presence of CN− ions unequivocally has been determined by observation of a sharp resonance at 2075 cm−1 in the single‐crystal raman spectrum.
Synthese und Charakterisierung der Verbindungen AIrP (A: La – Nd; Sr)
Authors: Löhken Anke , Reiß Guido J. , Johrendt Dirk , Mewis Albrecht
Published: April 2005

Synthesis and Characterization of the Compounds AIrP (A: La – Nd; Sr)

LaIrP (a = 4.149(2), c = 14.278(6) Å), CeIrP (a = 4.048(2), c = 14.288(11) Å), PrIrP (a = 4.069(2), c = 14.206(9) Å), and NdIrP (a = 4.065(1), c = 14.221(9) Å) are isotypic and crystallize in accordance with the structure determination (single crystal data) with the LaPtSi type structure (I41md; Z = 4). The Ir and P atoms are linked to a three‐dimensional network with a trigonal planar environment, whereas the rare‐earth metal atoms are located in the holes (coordination number 12). We show by DFT band structure calculations, why LaIrP prefers the LaPtSi type structure and not the AlB2 type. SrIrP (a = 6.325(1) Å) was investigated by powder methods and crystallizes with the LaIrSi type structure (P213; Z = 4). The Ir and P atoms are coordinated trigonally and form a three‐dimensional framework with the Sr atoms in the gaps (coordination number 17). The compounds were synthesized by heating mixtures of the elements at 1100 °C.
On the Tammann–Rule
Authors: Merkle Rotraut , Maier Joachim
Published: April 2005

The validity of Tammann's rule is related to the fact that the unavoidable thermal generation of point defects leads to defect‐defect interactions and finally to a breakdown of the structure. It is shown that the onset of this defect avalanche, which can be estimated by a cube root law, roughly corresponds to the Tammann temperature. The investigation of simple compounds corroborates this picture and also the observation of a critical defect concentration. Examples are given that Tammann's rule can be used to systematically search for new solid electrolytes.
Neue Barium‐Antimonid‐Oxide mit den Zintl‐Ionen [Sb]3−, [Sb2]4− und [Sbn]n−
Authors: Boss Michael , Petri Denis , Pickhard Frank , Zönnchen Peter , Röhr Caroline
Published: April 2005

New Barium Antimonide Oxides containing Zintl Ions [Sb]3−, [Sb2]4−, and [Sbn]n−

A new kind of chiral chains [Sbn]n− and O2− ions tetrahedrally coordinated by Ba are the characteristic anions in Ba3[Sb4][O] (monoclinic, space group P21/c, a = 696.4(2), b = 1280.7(3), c = 1294.1(3) pm, β = 112.39(1)°, Z = 4, R1 = 0.0399). Similarly, in RbBa4[Sb2][Sb][O], that crystallizes isotypic with KBa4[Sb2][Sb][O] (stuffed Cr5B3‐Typ, tetragonal, space group I4/mcm, a = 893.7(4), c = 1642.7(9) pm, Z = 4, R1 = 0.0508), the oxide ions occupy tetrahedral voids. The Zintl ions in this case are isolated [Sb]3− anions and dumbbells [Sb2]4− respectively. The new hydrid‐oxides Ba8[M]4[O][H]2 (M=Sb/Bi, tetragonal, space group I4/mmm, a = 515.34(12)/519.12(12), c = 3791.7(3)/3837.6(3) pm, Z = 4, R1 = 0.0319/0.0460) and Rb2Ba6[Sb2]2[Sb][O][H] (tetragonal, space group I4/mcm, a = 879.71(4), c = 2742.4(2) pm, Z = 4, R1 = 0.0592) can be structurally derived from the oxides Ba4Sb2O and RbBa4[Sb2][Sb][O] by intercalation (chemical twinning) of hydride antimonides. The synthesis of these air sensitive compounds exhibiting dark metallic luster was performed from melts of elemental Rb, Ba and Sb/Bi using Sb2O3/Bi2O3, BaH2 and Ba(OH)2 as sources for oxide/hydride. The detailed comparison of the structures and the results of FP‐LAPW band structure calculations show that the title compounds are electron precise Zintl phases with distinct band gaps.
Electron Holography, a Versatile Tool for Characterization of Materials: Fluoroapatite‐Gelatine‐Composites, SiC and SiO2
Authors: Simon Paul , Lichte Hannes , Mönter Damian , Reschetilowski Wladimir , Valera Anibal , Carrillo‐Cabrera Wilder
Published: April 2005

In recent years, electron holography developed into a powerful tool in materials characterisation. It allows to measure electrical or magnetic micro‐ and nanofields. Besides this, areas of different chemical composition, density or thickness can be distinguished without artefacts, such as lattice displacements or Fresnel fringes.

In this report, a short description of the method is given and new applications of electron off‐axis holography in the determination of density or thickness differences are presented. In composite biominerals, due to density variations we could clearly reveal the structure of the organic part of these aggregates. Further on, differences of domain sizes and porosities in para‐crystalline SiC were detected, which play a decisive role for their optical and electronic properties. Phase images of mesoporous silica clearly show the hexagonal and lamellar shape of the porosities without blurring. Thus, width and thickness of the walls can be determined, which is hardly achieved with other methods.
Ag12Te6S: A Contribution to Open Problems in the Crystal Chemistry of Complex Non‐Metallic Filled Frank‐Kasper Phases
Authors: Mikus H. , Deiseroth H. J.
Published: April 2005

The air stable gray‐metallic Ag12Te6S is a substitution variant of synthetic Ag5−xTe3 (mineral name: stutzite, range of x controversial) crystallizing in the space group $P{\bar 6}$ (Z = 3) with lattice parameters a = 13.413(2) Å, c = 8.452(2) Å. All non‐metal atoms in this complex solid are topologically arranged like Zr and Al atoms in the Frank‐Kasper phase Zr4Al3 forming a system of interpenetrating Frank‐Kasper polyhedra with coordination numbers 12, 14 and 15. Symmetry relations between stutzite, Zr4Al3 and the title compound are presented. The interpenetration of Frank‐Kasper polyhedra results in a complex three‐dimensional network of distorted tetrahedra intimately connected by common corners, edges, and faces (tetrahedral or topological close packing). A specific disorder problem which complicates the compositional and structural characterization of stutzite considerably is not present in the title compound. Whereas stutzite contains single Te2−, (Te2)2−(ordered), and additional (Te2)2− sharing a poorly resolved number of common crystallographic positions with further Te2−, in the title compound ordered Te2−, (Te2)2−, and S2− are found only, not leaving any ambiguity for the number of charge compensating Ag+ ions. Except of a new silver position in close vicinity to the S2−, the distribution of the strongly disordered Ag+ in the title compound is only slightly different from that in stutzite and is not further discussed in this paper. Literature reports concerning a c‐axis doubling cannot be confirmed neither for stutzite nor for the title compound.
Nanocrystalline Ferrites Prepared by Mechanical Activation and Mechanosynthesis
Authors: Šepelák Vladimir , Bergmann Ingo , Kipp Stephan , Becker Klaus Dieter
Published: April 2005

At present, the high‐energy milling method becomes widely used for the preparation of nanocrystalline materials due to its relative simplicity and availability. In this research report, selected examples are presented of the preparation of nanoscale spinel ferrites by mechanical activation and mechanosynthesis. Nanosized particles of mechanochemically prepared spinel ferrites are structurally and magnetically disordered due to the non‐equilibrium cation distribution and non‐collinear spin arrangement. As a consequence, they exhibit interesting physical and chemical properties markedly different from those of their bulk counterparts. Several interesting features are involved in the work, e.g., superparamagnetism, an enhanced chemical reactivity, an irreversible magnetic behaviour, an enhanced magnetic ordering temperature, and an altered (reduced or enhanced) saturation magnetization in comparison with the corresponding bulk materials. Taking into account the considerable relevance of the thermal stability of nanoscale complex oxides to nanoscience and nanotechnology, results on the response of mechanochemically prepared spinel ferrites to changes in temperature will also be presented.
Zur Stabilisierung von Suboxidphasen durch Carbidionen: Die Kristallstruktur von Sr21Si2O5C6
Authors: Knoth Markus , Rößler Ute , Eisenmann Brigitte
Published: April 2005

On the Stabilization of Suboxide Phases by Carbide Ions: The Crystal Structure of Sr21Si2O5C6

Metallic brass‐coloured crystals of Sr21Si2O5C6were isolated from samples starting from the educts Sr : SiO : C = 21 : 2 : 6 heated under argon atmosphere in corundum crucibles up to 1150 K. The air‐sensitive compound crystallizes in the cubic system, space group $F d \: \overline{\mathit{3}} \: m, a$ = 1914,56(19) pm, Z = 8. In the crystal structure the Si, O and C atoms are coordinated only by Sr atoms forming distorted icosahedra around Si and distorted octahedra around O and C. The compound can be classified as an electron precise Zintl phase according to (Sr2+)21(Si4−)2(O2−)5(C4−)6.
Solvothermalsynthese: Synthese und Strukturaufklärung der Nb‐Cu‐S‐Komplexe [NbCu5S4Cl2(dppm)4]·5CH3CN und (NEt4)2[Nb10Cu12Cl4S30(dpppr)6]·6MeCN
Authors: Feuerhake Robert , Reiser Benjamin K. H. , Sommer Heino , Fenske Dieter
Published: April 2005

Solvothermal Synthesis: Synthesis and Structure Elucidation of the Nb‐Cu‐S Complexes [NbCu5S4Cl2(dppm)4]·5CH3CN and (NEt4)2[Nb10Cu12Cl4S30(dppr)6]·6MeCN

In the presence of bis(diphenylphosphanyl)propane (dppr) and bis(diphenylphosphanyl)methane (dppm), the solvothermal reaction of the thioniobate (NEt4)4[Nb6S17]·3MeCN with CuCl gives the new niobium copper sulfides [NbCu5S4Cl2(dppm)4]· 5CH3CN (1) and (NEt4)2[Nb10Cu12Cl4S30(dpppr)6]·6MeCN (2). The molecular structures of these compounds are determined by the chelate effect of the bidental phosphine ligands.
Chemical Diversity in View of Property Generation by a New Combinatorial Approach
Authors: Hulliger Jürg , Aslam Awan Muhammad , Trusch Bernhard , Samtleben Till A.
Published: April 2005

Even the exploration of the phase space given by a large number N (N ≤ 61) of components but a limited number q (q ≤ 6) of elements Ei in e.g. metal oxides Ex1>(1)Ex2(2)…Exq(q)Oy is a demanding task and needs a combinatorial approach which, by setting up starting conditions for solid‐state reactions, is taking favour of efficient combinatorial functions. Estimations showed that within a single sample prepared by mixing N starting components, the number of local reaction centres (configurations) is exceeding the number of phase systems. A huge amount of about 1012 starting grains for a sample of one cm3 provides population of each configuration many times. The distribution for the grain size and the number of grains building up a configuration allow to explore compositional fields in phase diagrams of the order q. The single sample concept (SSC) is particularly of interest for property oriented syntheses, where e.g. magnetic materials are produced in minor quantities. Magnetic chromatography is applied to extract ferromagnetic materials formed by the SSC. A horizontal separator is presented and applied to extract new ferromagnetic Fe‐based oxides from SSC reaction mixtures.
Synthesis and Characterization of Cobalt Monosilicide (CoSi) with CsCl Structure Stabilized by a β‐SiC Matrix
Authors: Walter Dirk , Karyasa I W.
Published: April 2005

In the Co/Si/C system a new CoSi (CsCl type) modification besides ß‐SiC and carbon is observed after a sintering process of the elements at a temperature of 1400 °C (4 h; vacuum). The structure of the cobalt monosilicide (CsCl type) was determined by X‐ray powder diffraction methods and subsequent Rietveld refinement. CoSi (CsCl type) crystallizes in the cubic space group $Pm{\bar 3}m$ (no. 221) with the lattice parameters a = 281.62(2) pm (V= 22.337(7) × 106 pm3). However, in the Co/Si system only the well known ε‐CoSi (FeSi type) is observed at the same reaction conditions. It is supposed that β‐SiC takes an important role in stabilizing the CoSi (CsCl type). Electron microscopy experiments (SEM and EDX) confirm that the cobalt monosilicide is surrounded by a β‐SiC matrix containing a small amount of carbon. The thermal stability of the synthesized samples was studied. Furthermore, the density of states (DOS) was calculated.
Characterization of Mo‐V‐W Mixed Oxide Catalysts by ex situ and in situ X‐Ray Absorption Spectroscopy
Authors: Schimanke Guido , Martin Manfred , Kunert Jan , Vogel Herbert
Published: April 2005

Mixed oxides in the system Mo‐V‐W‐O are important catalysts for partial oxidation reactions, e.g. the partial oxidation of acrolein to acrylic acid. Multiphase catalysts of the overall composition Mo8V2WyOx were prepared by spray drying and crystallization. The charge states of the potential catalytic centers Mo, V and W were investigated by ex situ X‐ray absorption spectroscopy (XAS). In the as prepared samples the cations exist essentially as Mo6+, V5+ and W6+. Exposure of the as prepared samples to acrolein results in a reduction of both Mo6+ and V5+ whereas W6+ is inert. Re‐oxidation with oxygen causes a reversible oxidation of Mo and V. The kinetics of the reduction and re‐oxidation processes of the catalyst samples was studied at a temperature of 500 °C by in situ X‐ray absorption spectroscopy at the Mo K‐edge with carbon monoxide and oxygen as reducing and oxidizing gases. The in situ experiments show that the reduction of Mo6+ in CO is about one order of magnitude slower than the subsequent re‐oxidation in oxygen.
Synthesis of Empirical and Theoretical Approaches Toward the Establishment of GBAS σpr_gnd
Authors: Pervan Boris , Sayim Irfan , Khanafseh Samer
Published: April 2005

The objective of this paper is to describe recent progress in the area of the Ground Based Augmentation System (GBAS) σpr_gnd establishment to ensure aircraft precision approach navigation integrity. In particular, this paper details: (1) the development and testing of a new adaptive binning algorithm for processing GBAS reference station empirical data to account for ranging error non-stationarity; (2) an introduction of a practical empirical method to quantify and compensate for the effects of seasonal variations of ranging error; and (3) the synthesis of these empirical results with existing theoretical ground-multipath models toward a quantitative establishment σpr_gnd for GBAS.
Navigation Kalman Filter Design for Pipeline Pigging
Authors: Shin Eun-Hwan , El-Sheimy Naser
Published: April 2005

The paper discusses the development of an adaptive Kalman filter for pipeline surveying applications. Various measurement models are developed and numerically tested using a real natural gas pipeline dataset. Since, for tactical-grade IMUs, odometer-derived velocity measurements alone cannot yield good results, two non-holonomic constraints are augmented to make the three-direction measurement model. Smoothing computation is also applied to yield the best trajectory using all the information contained in the past, current and future measurements. The trajectory errors are within 10–20 m for extreme cases, and within 10 m for most cases. RMS of the trajectory errors is expected to be about 2·5 m.
Implications of Ionospheric Scintillation for GNSS Users in Northern Europe
Authors: Aquino Marcio , Moore Terry , Dodson Alan , Waugh Sam , Souter Jock , Rodrigues Fabiano S.
Published: April 2005

Extensive ionospheric scintillation and Total Electron Content (TEC) data were collected by the Institute of Engineering Surveying and Space Geodesy (IESSG) in Northern Europe during years of great impact of the solar maximum on GNSS users (2001–2003). The ionospheric TEC is responsible for range errors due to its time delay effect on transionospheric signals. Electron density irregularities in the ionosphere, occurring frequently during these years, are responsible for (phase and amplitude) fluctuations on GNSS signals, known as ionospheric scintillation. Since June 2001 four GPS Ionospheric Scintillation and TEC Monitor receivers (the NovAtel/AJ Systems GSV4004) have been deployed at stations in the UK and Norway, forming a Northern European network, covering geographic latitudes from 53° to 70° N approximately. These receivers compute and record GPS phase and amplitude scintillation parameters, as well as TEC and TEC variations. The project involved setting up the network and developing automated archiving and data analysis strategies, aiming to study the impact of scintillation on DGPS and EGNOS users, and on different GPS receiver technologies. In order to characterise scintillation and TEC variations over Northern Europe, as well as investigate correlation with geomagnetic activity, long-term statistical analyses were also produced. This paper summarises our findings, providing an overview of the potential implications of ionospheric scintillation for the GNSS user in Northern Europe.
Exteriorisation of the heart in two siblings
Authors: Assaqqat Mervat A. , Al-Fayyadh Majid I. , Bulbul Ziad R.
Published: April 2005

We report two siblings with isolated ectopic hearts. Neither child had associated congenital diseases. To the best of our knowledge, this is the first reported familial occurrence of ectopic hearts.
The influence of measured versus assumed uptake of oxygen in assessing pulmonary vascular resistance in patients with a bidirectional Glenn anastomosis
Authors: Shanahan Christine L. , Wilson Nigel J. , Gentles Tom L. , Skinner Jonathan R.
Published: April 2005

Aims: To determine the accuracy of data relating to pulmonary vascular resistance data in patients with a bidirectional Glenn anastomosis as calculated using predicted versus measured uptake of oxygen. Methods: We studied retrospectively the data from 33 patients with a bidirectional Glenn anastomosis who underwent cardiac catheterisation prior to surgery to complete the Fontan circulation. Their weight ranged from 5.4 to 51.7 kg, and they were aged up to 12 years. Uptake of oxygen was measured using the Deltatrac II metabolic monitor. From the calculated indexed pulmonary vascular resistance, cases were stratified according to the risk of failure of the subsequent Fontan circulation. The six patients with a resistance of greater than 4 Um2 were deemed at high risk, the six with a resistance from 3 to 4 Um2 at moderate risk, and the 21 patients with a resistance less than 3 Um2 at low risk. Uptake of oxygen was also estimated from the predictive formulas of Lindahl, Lundell et al. and LaFarge and Miettinen. The indexed resistance was similarly calculated using these formulas and a comparable stratification of risk made from this data. Results: The predicted values for uptake of oxygen were consistently higher than those measured, leading to an underestimation of indexed resistance, with mean difference between −0.62 and −1.57 Um2. This difference resulted in misclassification of between five and nine of the 12 patients considered at moderate or high risk as being at low-risk. No other haemodynamic data could reliably separate the subjects deemed at low-risk from those considered to be at high-risk. A transpulmonary gradient of greater than 7 mm of mercury was found to be 100 percent specific for elevated indexed resistance, but only 60 percent sensitive. Conclusions: In patients with bidirectional Glenn anastomoses, all formulas based on predictive uptake of oxygen lead to underestimation of the true indexed pulmonary vascular resistance, to an extent that could significantly influence clinical decision-making. The transpulmonary gradient is not a reliable surrogate for indexed pulmonary vascular resistance.
Replacement of the aortic valve after the arterial switch operation
Authors: Alexi-Meskishvili Vladimir , Photiadis Joachim , Nürnberg Jan-Hendrik
Published: April 2005

An 11-month-old infant had undergone a primary arterial switch operation, including the Lecompte maneuver, for correction of discordant ventriculo-arterial connections and closure of an accompanying ventricular septal defect.

At discharge, there were no signs of aortic valvar incompetence. Regurgitation across the aortic valve was detected first at the age of 2 years, and then increased progressively, as documented by serial echocardiographic studies. There had been no history of bacterial endocarditis. At the age of 10 years, echocardiography revealed severe aortic valvar incompetence. At operation, the aortic valve had three leaflets, all of which were short, with very restricted movement. Absence of sufficient leaflet tissue precluded a durable valvar reconstruction, so the aortic valve was replaced with a 21 mm mechanical prosthesis. Histological examination of the removed leaflets revealed nodular swelling due to mucous changes of the matrix, as well as fibrous alteration and formation of scar tissue, including areas of fibroblastic and capillary proliferation. There were no signs of calcification or acute inflammatory changes. Improvement of left ventricular function was observed both early postoperatively and later on. Our observation shows that aortic valvar incompetence after an arterial switch operation can be caused by degenerative changes of the neo-aortic leaflets, which prevent plastic reconstruction of the valve, necessitating valvar replacement.
Histopathological follow-up after bailout stenting for early postoperative stenosis of a central aorto-pulmonary shunt
Authors: Peuster Matthias , Wohlsein Peter , Schnakenburg Christian von
Published: April 2005

We treated a neonate with pulmonary atresia and a ventricular septal defect complicated by straddling of the atrioventricular valves by constructing a central aorto-pulmonary shunt. The postoperative course was complicated by obstruction of the shunt, which was treated by implantation of a coronary stent. Six months after the stenting, a Glenn anastomosis was created and the stented shunt removed. Analysis showed that the shunt was completely covered by a vascularized neointima. The stent had not produced injury to the shunt, with struts of the stent covered nicely by neoendothelium, with sparse inflammation surrounding the artificial implants.
Ischemia due to peripartum cardiomyopathy threatening loss of a leg
Authors: Gagne Paul J. , Newman John B. , Muhs Bart E.
Published: April 2005

Ischemia of the leg in a peripartum female is an uncommon condition. Paradoxical arterial embolisation, and arterial dissection, are rarely encountered but recognized causes of this clinical condition. Peripartum cardiomyopathy is a rare life-threatening cardiac condition that can foster intracardiac thrombosis and produce peripheral vascular complications through embolization. We present here the case of a young, healthy, postpartum female who developed acute ischemia of the left leg, and asymptomatic arterial insufficiency of the right lower leg, as the presenting symptoms of peripartum cardiomyopathy, highlighting the fact that ischemia threatening the loss of a limb can be the initial manifestation of peripartum cardiomyopathy.
Contrasting structural and P‐T evolution of tectonic units in the southeastern Betics: Key for understanding the exhumation of the Alboran Domain HP/LT crustal rocks (western Mediterranean)
Authors: Booth‐Rea G. , Azañón J. M. , Martínez‐Martínez J. M. , Vidal O. , García‐Dueñas V.
Published: April 2005

Thermobarometry using mica‐chlorite local equilibria and structural analysis of three tectonic units of the Alpujarride complex in the southeastern Betics indicate that rocks that underwent low‐pressure/low‐temperature metamorphism are found below higher‐grade blueschist facies rocks. Moreover, the high‐pressure/low‐temperature (HP/LT) units underwent contrasting (P‐T) and structural evolutions. The structurally highest unit was exhumed in a typical postorogenic high‐temperature geothermal context in the andalusite stability field, while the intermediate unit was exhumed following a cooling and decompression P‐T path within the kyanite stability field. The superposition of the three units occurred during the lower Miocene related with north directed brittle‐ductile shear zones and associated north vergent overturned folds, after postorogenic exhumation of the top unit. The coexistence of thrusting with lower and middle Miocene brittle extensional systems active in shallower levels of the Alboran orogenic wedge implies that extension was synorogenic. These data strengthen the hypothesis that rocks thinned by postorogenic extension during the latest Oligocene and lower Miocene were entrained in the lower to middle Miocene Alboran orogenic wedge.
A global cloud‐resolving simulation: Preliminary results from an aqua planet experiment
Authors: Tomita H. , Miura H. , Iga S. , Nasuno T. , Satoh M.
Published: April 2005

Results from global simulations using a nonhydrostatic icosahedral‐grid AGCM with cloud‐resolving resolutions on an aqua planet are discussed. Results depend on the resolution. Simulations with grid intervals of 7 km and 3.5 km include many realistic features in the tropics: hierarchical cloud structures, a Madden‐Julian Oscillation (MJO)‐like intraseasonal oscillation, and diurnal precipitation cycles. Global cloud‐resolving simulations show promise for future climate research. Such models avoid the liabilities associated with cumulus parameterization.
Quantum kinetic energy densities: An operational approach
Authors: Muga J. G. , Seidel D. , Hegerfeldt G. C.
Published: April 2005

We propose and investigate a procedure to measure, at least in principle, a positive quantum version of the local kinetic energy density. This procedure is based, under certain idealized limits, on the detection rate of photons emitted by moving atoms which are excited by a localized laser beam. The same type of experiment, but in different limits, can also provide other non-positive-definite versions of the kinetic energy density. A connection with quantum arrival time distributions is discussed.
The structural and electronic properties of nanostructured Ce1−x−yZrxTbyO2 ternary oxides: Unusual concentration of Tb3+ and metal↔oxygen↔metal interactions
Authors: Wang Xianqin , Hanson Jonathan C. , Rodriguez José A. , Belver Carolina , Fernández-García Marcos
Published: April 2005

Ceria-based ternary oxides are widely used in many areas of chemistry, physics, and materials science. Synchrotron-based time-resolved x-ray diffraction, x-ray absorption near-edge spectroscopy (XANES), Raman spectroscopy, and density-functional calculations were used to study the structural and electronic properties of Ce–Zr–Tb oxide nanoparticles. The nanoparticles were synthesized following a novel microemulsion method and had sizes in the range of 4–7nm. The Ce1−x−yZrxTbyO2 ternary systems exhibit a complex behavior that cannot be predicted as a simple extrapolation of the properties of Ce1−xZrxO2, Ce1−xTbxO2, or the individual oxides (CeO2, ZrO2, and TbO2). The doping of ceria with Zr and Tb induces a decrease in the unit cell, but there are large positive deviations with respect to the cell parameters predicted by Vegard’s rule for ideal solid solutions. The presence of Zr and Tb generates strain in the ceria lattice through the creation of crystal imperfections and O vacancies. The O K-edge and Tb LIII-edge XANES spectra for the Ce1−x−yZrxTbyO2 nanoparticles point to the existence of distinctive electronic properties. In Ce1−x−yZrxTbyO2 there is an unexpected high concentration of Tb3+, which is not seen in TbO2 or Ce1−xTbxO2 and enhances the chemical reactivity of the ternary oxide. Tb↔O↔Zr interactions produce a stabilization of the Tb(4f,5d) states that is responsible for the high concentration of Tb3+ cations. The behavior of Ce1−x−yZrxTbyO2 illustrates how important can be metal↔oxygen↔metal interactions for determining the structural, electronic, and chemical properties of a ternary oxide.
Quantum dynamics of the Li+HF→H+LiF reaction at ultralow temperatures
Authors: Weck P. F. , Balakrishnan N.
Published: April 2005

Quantum-mechanical calculations are reported for the Li+HF(v=0,1,j=0)→H+LiF(v′,j′) bimolecular scattering process at low and ultralow temperatures. Calculations have been performed for zero total angular momentum using a recent high-accuracy potential-energy surface for the X2A′ electronic ground state. For Li+HF(v=0,j=0), the reaction is dominated by resonances due to the decay of metastable states of the Li⋯F–H van der Waals complex. Assignment of these resonances has been carried out by calculating the eigenenergies of the quasibound states. We also find that while chemical reactivity is greatly enhanced by vibrational excitation, the resonances get mostly washed out in the reaction of vibrationally excited HF with Li atoms. In addition, we find that at low energies, the reaction is significantly suppressed due to the less-efficient tunneling of the relatively heavy fluorine atom.
Highly polarized electrons from GaAs–GaAsP and InGaAs–AlGaAs strained-layer superlattice photocathodes
Authors: Nishitani T. , Nakanishi T. , Yamamoto M. , Okumi S. , Furuta F. , Miyamoto M. , Kuwahara M. , Yamamoto N. , Naniwa K. , Watanabe O. , Takeda Y. , Kobayakawa H. , Takashima Y. , Horinaka H. , Matsuyama T. , Togawa K. , Saka T. , Tawada M. , Omori T. , Kurihara Y. , Yoshioka M. , Kato K. , Baba T.
Published: April 2005

GaAs–GaAsP and InGaAs–AlGaAs strained-layer superlattice photocathodes are presented as emission sources for highly polarized electron beams. The GaAs–GaAsP cathode achieved a maximum polarization of 92(±6)% with a quantum efficiency of 0.5%, while the InGaAs–AlGaAs cathode provides a higher quantum efficiency (0.7%) but a lower polarization [77(±5)%]. Criteria for achieving high polarization using superlattice photocathodes are discussed based on experimental spin-resolved quantum efficiency spectra.
Measurement of the refractive index of a magnetic fluid by the retroreflection on the fiber-optic end face
Authors: Pu Shengli , Chen Xianfeng , Chen Yuping , Liao Weijun , Chen Lijun , Xia Yuxing
Published: April 2005

A simple method based on the retroreflection on the fiber-optic end face is developed to measure the refractive index of a magnetic fluid in this letter. The measuring principle, accuracy, and sensitivity of this method are analyzed theoretically, and high precision and resolution can be achieved in principle. Experimental measurements are done to investigate the concentration and temperature dependent refractive index of the magnetic fluid. The linear dependence relation is obtained for both cases. The thermo-optical coefficient of the magnetic fluid is measured to be around −2.4×10−4°C−1.
An approach to the design of highly selective resonant-cavity-enhanced photodetectors
Authors: Ramam A. , Chowdhury G. K. , Chua S. J.
Published: April 2005

The information capacity of a communication system employing a wavelength-division multiplexing scheme can be increased by reducing the free spectral range between different signals, reducing the full width at half maximum (FWHM), and detecting these closely spaced channels. After critically analyzing the design parameters of existing resonant-cavity-enhanced (RCE) p–i–n photodetectors, we have determined that more closely spaced channels can be detected either by increasing the length of a RCE p–i–n detector or by reducing the stop-band width of the bottom mirror. A masking procedure is described to determine the maximum cavity length attainable for any bottom distributed Bragg reflector (DBR) materials so that photodetector filters and detects only one wavelength, being insensitive to all other wavelengths. The optimized cavity length of single wavelength selective RCE detector operating at 1.3μm using 42 12 pairs of InAlGaAs∕InP as a bottom DBR is 7.5μm and its theoretical FWHM is 2.5nm.
Self-stabilized and dispersion-compensated passively mode-locked Yb:Yttrium aluminum garnet laser
Authors: Agnesi A. , Guandalini A. , Reali G.
Published: April 2005

Self-stabilized passive mode-locking of a diode-pumped Yb:yttrium aluminum garnet laser with a semiconductor saturable absorber was achieved using an off-phase-matching second-harmonic crystal. According to the numerical model, such a condition is accomplished by self-defocusing in the nonlinear crystal in the presence of positive intracavity dispersion. Robust mode locking with Fourier-limited 1.0-ps pulses was obtained, whereas mode locking, unassisted by the nonlinear crystal, yielded 2.2-ps pulses, with the laser operating near the edge of the stability region in order to minimize the saturation energy of the semiconductor device.
In situ nanointerconnection for nanoelectronics via direct auto-catalytic lateral growth
Authors: Lee Yun-Hi , Jang Y. T. , Ju B. K.
Published: April 2005

The lateral reduction of interconnection in nanoelectronics will require a one-dimensional metallic nanointerconnector. This work presents an achievement of the all-chromium (Cr) nanointerconnection architecture, an approach to nanointerconnection, in which both electrodes and connecting lines are realized by the same Cr using the autocatalytic function of Cr without any additional lithography. Especially observed was the time evolution of the directional lateral growth of Cr nanowires using a dc electric field during the in situ growth of Cr nanowires. Finally, it was confirmed that the in situ-grown Cr nanobridge could act as an electrode interconnector due to its good metallic current-voltage characteristics.
Formation of ohmic contacts for both holes and electrons to organic semiconductor films
Authors: Suemori Kouji , Yokoyama Masaaki , Hiramoto Masahiro
Published: April 2005

Ohmic contacts for both holes and electrons were formed on naphthalene tetracarboxylic anhydride films at platinum-doped p-type film/metal and sodium-doped n-type film/metal junctions, respectively. The injection current density reached 4Acm−2 at a low bias field of 6×104Vcm−1. Platinum was revealed to be a candidate for a permanent dopant that can act as an electron acceptor in the formation of p-type organic semiconductors.