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Evaluating a quantitative IT maturity self-assessment approach: Does it give a good way of the as-is state?

It has become increasingly recognized that IT organizations must ensure that IT services are aligned to business needs and actively support them. Therefore, the internal IT service management processes are under constant improvement. Information Technology Infrastructure Library (ITIL) is the most commonly adopted framework for IT service management. The recommendation is to start an ITIL implemenIt has become increasingly recognized that IT organizations must ensure that IT services are aligned to business needs and actively support them. Ther efore, the internal IT service management processes are under constant improvement. Information Technology Infrastructure Library (ITIL) is the most commonlyadopted framework for IT service management. The r ecommendation is to start an ITIL impleme

Synthesis of high-quality, well-characterized CaAlFe-layered triple hydroxide with the combination of dry-milling and ultrasonic irradiation in aqueous solution at elevated temperature

The combination of mechanochemical and ultrasonic treatment was applied to synthesize CaAlFe-layered triple hydroxides with carbonate or chloride anions in the interlamellar space. The optimal parameters of the preparation were explored by altering the initial ratio of the metal ions and the temperature of ultrasonic irradiation. The resulting triple hydroxides were characterized by X-ray diffract

Mechanochemical synthesis and intercalation of Ca(II)Fe(III)-layered double hydroxides

A mechanochemical method (grinding the components without added water - dry grinding, followed by further grinding in the presence of minute amount of water or NaOH solution - wet grinding) was used in this work for the preparation and intercalation of CaFe-layered double hydroxides (LDHs). Both the pristine LDHs and the amino acid anion (cystinate and tyrosinate) intercalated varieties were prepa

Mn(II)-amino acid complexes intercalated in CaAl-layered double hydroxide - Well-characterized, highly efficient, recyclable oxidation catalysts

Intercalated composite materials were prepared with CaAl-layered double hydroxide as the host and Mn(II)-amino acid (l-cysteine, l-histidine and l-tyrosine) complex anions as the guest. Two methods (intercalation of the ligand first followed by constructing the complex; preforming the complex first, then introducing it among the layers of the host) and optimization of the auxiliary conditions were

Crystal structure of carbon dioxide at high pressure : "Superhard" polymeric carbon dioxide

The crystal structures of two molecular phases (I and III) and a polymeric phase (V) of CO2 have been investigated to 60 GPa. CO2-1 (Pa3) transforms to CO2-III (Cmca) at 12 GPa with almost no change of density. Although CO2-III persists in Cmca to at least 60 GPa at ambient temperature, it transforms when heated to 1800 K above 40 GPa to tridymite (P212121) CO2-V with 15.3% volume change. Each car

Phase transition in Cs2KMnF6 : Crystal structures of low- and high-temperature modifications

Crystalline Cs2KMnF6, when prepared below 500°C, adopts a tetragonal elpasolite structure type. Differential scanning calorimetric investigations indicated that Cs2KMnF6 undergoes a phase transition from the low-temperature tetragonal phase (LT) to a high-temperature phase (HT) at about 530°C. Single crystals of the new HT phase could be obtained by annealing a crystalline LT specimen at 600°C fol

High-pressure studies of Cs2CuCl4, and Cs2CoCl4 by X-ray diffraction methods

Single crystals of Cs2CuCl4 and Cs2CoCl4 have been investigated at high pressures by X-ray diffraction techniques, using a diamond anvil cell. Increasing the pressure to just below 40 kbar caused the crystallinity of Cs2CuCl4 to deteriorate rapidly. This was accompanied by a color change from yellow/orange at lower pressures to deep red, suggesting, e.g., a major change of the coordination geometr

Structural stability and equation of state of simple-hexagonal phosphorus to 280 GPa : Phase transition at 262 GPa

A structural phase transition and the equation of state of the simple-hexagonal (sh) phase, P-V, of phosphorus were investigated at pressures up to 280 GPa using monochromatic synchrotron x-ray diffraction. The P-V phase, which was stable above 137 GPa, has shown a structural transition to a higher-pressure phase, P-VI, above 262 GPa, while the c/a ratio of the sh phase slightly increased with inc

High-pressure studies of the cubic to rhombohedral transformation in NbO2F

The Pm3̄m to R3̄c high-pressure transition of NbO2F has been studied in detail using diamond anvil cells and synchrotron X-ray radiation. The transition starts at 0.28 GPa and is complete at 0.65 GPa. The bulk modulus for the cubic phase became 24.8 (11) GPa, which is roughly two times higher than for the rhombohedral phase.

Bulk modulus and high-pressure crystal structures of tetrakis(trimethylsilyl)methane C[Si(CH3)3]4 determined by X-ray powder diffraction

The pressure dependence of the crystal structure of cubic tetrakis(trimethylsilyl)methane C[Si(CH3)3]4 (TC) (P 10 GPa) a transformation is observed into a c.c.p. structure that is different from the face-centred-cubic structure at ambient conditions. A non-linear compression behaviour is observed, which could be described by a Vinet relation in the range 0.28-4.8 GPa. The extrapolated bulk modulu

High-pressure transitions of trigonal α-ZrMo2O8

High-pressure synchrotron x-ray powder-diffraction studies show that trigonal α-ZrMo2O8 transforms to a monoclinic symmetry phase (δ-ZrMo2O8) at 1.06-1.11 GPa. The space group was determined to C2/m. A further high-pressure transition from the monoclinic δ to a triclinic ε phase occur at 2.0-2.5 GPa (space group P1 or P1). Both transformations are reversible. The volume compressibilities are simil

High-pressure structures of α- and δ-ZrMo2O8

In situ high-pressure synchrotron X-ray powder diffraction studies of trigonal α-ZrMo2O8, zirconium molybdate, have been performed from ambient conditions to 1.9 GPa, over the α-δ phase transition at 1.06-1.11 GPa. The monoclinic structure of δ-ZrMo2O8, stable between 1.1 and 2.5 GPa at 298 K, has been solved by direct methods and refined using the Rietveld method. Significant distortions of the Z

Pressure-induced phase transitions in α-ZrMo2O8

We report high-pressure Raman, infrared (IR), and optical-absorption spectra of α-ZrMo2O8 (trigonal) up to 38 GPa at room temperature. The spectroscopic studies are consistent with diffraction results that show that α-ZrMo2O8 transforms into δ-ZrMo2O8 (monoclinic) at about 1 GPa and the δ phase converts to the ε phase (triclinic) at about 2.0 GPa. Optical-absorption measurements give an estimate o

High-pressure properties of TiP2O7, ZrP2O7 and ZrV2O7

High-pressure synchrotron X-ray powder diffraction studies of TiP2O7, ZrP2O7 and ZrV2O7 have been performed. The ZrV2O7 structure undergoes a reversible transition at 1.38-1.58 GPa from cubic α- to pseudo-tetragonal β-ZrV2O7 that displays an orthorhombic 2 × 3 × 3 supercell. At pressures above 4 GPa, ZrV2O7 becomes irreversibly X-ray amorphous. No such transformations are observed for TiP2O7 and Z