bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neue Formalismen zum Schätzen von Messunsicherheiten – Ein Beitrag zum Verknüpfen und Fortpflanzen von Messfehlern (A new Approach for the Estimation of Measurement Uncertainties – A Contribution to the Combination and Propagation of Errors of Measurement)
Authors: Grabe M. 
Published: August 2006

Auf Empfehlung der International Organization for Standardization (ISO) wurde mit dem Guide to the Expression of Uncertainty in Measurement ein Konzept zum Schätzen von Messunsicherheiten vorgelegt. Der Guide wurde seitens der nationalen metrologischen Staatsinstitute der Welt und zahlreicher anderer internationaler Organisationen als verbindlich erklärt.
In einem Übersichtsartikel Gedanken zur Revision der Gauß´schen Fehlerrechnung hat der Verfasser die Formalismen des Guide kritisch analysiert und ihnen ein alternatives Fehlermodell gegenübergestellt. Dessen wesentliche Kennzeichen sind nichterwartungstreue Schätzer – bedingt durch so genannte unbekannte systematische Messfehler – und der Rückgriff auf die Dichten von Fisher, Wishart und Hotelling. Die vorliegende Abhandlung detailliert die zum Guide alternativen Ideen zum Verknüpfen und Fortpflanzen von Messfehlern.
Doppel-Energie Röntgen-Computer-Tomographie in der Verfahrenstechnik (Dual-Energy X-ray Tomography in Process Engineering)
Authors: Strabel M. , Wirth K.-E. 
Published: August 2006

Abstract
Das tomographische Messverfahren unter Verwendung von Röntgenstrahlung wird schon seit vielen Jahren erfolgreich eingesetzt, um Strömungsstrukturen in zweiphasigen Gas/Feststoff-Strömungen zu untersuchen. Die Einführung der Doppel-Energie-Technik ermöglicht es, die Anwendbarkeit auch auf dreiphasige Systeme zu erweitern und Prozesse wie das Einspritzen von flüssigem Edukt in eine Gas/Feststoff-Wirbelschicht zu untersuchen oder den Reaktionsverlauf in dreiphasigen Blasensäulen besser zu verstehen. Messungen an statischen und dynamischen Testobjekten haben die Zuverlässigkeit des Messsystems bewiesen und demonstrieren die breite Anwendbarkeit der Doppel-Energie-Röntgen-Computer-Tomographie.
NMR in der Prozesskontrolle: Bildgebende und unilaterale NMR in weicher Materie (NMR for Process Control: Imaging and Localized NMR in Soft Matter)
Authors: Eymael R. , Blümich B. 
Published: August 2006

Abstract
Die Kernmagnetische Resonanz (engl.: Nuclear Magnetic Resonance, NMR) ist ein spektroskopisches Verfahren, das mit Radiofrequenz in magnetischen Feldern arbeitet. Bekannt ist vor allem die NMR-Spektroskopie, die in der Chemie als Standardmethode zur Strukturaufklärung eingesetzt wird, sowie die bildgebende Kernspintomographie, die heutzutage eine etablierte diagnostische Methode in der Medizin darstellt. Der Erfolg der medizinischen Bildgebung rührt von der relativ hohen NMR-Empfindlichkeit des Protons und von der Vielfalt an anwendbaren Kontrastmechanismen her, wodurch in heterogenen Objekten Strukturen sichtbar werden, die mit vielen anderen Methoden nicht aufgelöst werden können. Dieselben Möglichkeiten bieten sich für die Materialforschung, was die Produkt- und Prozesskontrolle insbesondere weicher Materialien wie Elastomere, Polymerschmelzen und Nahrungsmittel einschließt. Während der Einsatz der NMR zur chemischen Strukturanalyse hochgradig homogene Magnetfelder und damit eine kostspielige und empfindliche Technik erfordert, können viele Aspekte aus Materialforschung und Prozesskontrolle auch mit inhomogenen Magnetfeldern untersucht werden, wie sie durch einfache Permanentmagnete erzeugt werden. Dadurch lassen sich preiswerte Messsonden mit offener Geometrie realisieren. Der Hauptanwendungsbereich solcher unilateraler NMR-Konzepte liegt daher in der zerstörungsfreien Materialanalyse großer Objekte. Neben statischen Objekten können auch Strömungsvorgänge von Flüssigkeiten, granularen Medien oder komplexen Stoffgemischen verfolgt werden (Flow-NMR). Die Bereiche Flow-NMR und unilaterale NMR werden speziell im Hinblick auf die Anwendungen und Entwicklungen der NMR-MOUSE® (Mobile Universal Surface Explorer) angesprochen.
The chalcogenide phosphate apatites Ca10(PO4)6S, Sr10(PO4)6S, Ba10(PO4)6S and Ca10(PO4)6Se
Authors: Henning P.A. , Adolfsson E. , Grins J. 
Published: August 2006

Four new apatitic phases were prepared and their structures determined. The structure of Ca10(PO4)6S was refined from single crystal X-ray data and the structures of Sr10(PO4)6S, Ba10(PO4)6S and Ca10(PO4)6Se from powder X-ray data using the Rietveld method.
The four apatites are isostructural and crystallize in the trigonal space group P-3 with the chalcogenide ion positioned at (0 0 ½). The sulfoapatites show no ability to absorb H2S in the way that oxyapatite absorbs H2O at elevated temperatures. This can be attributed to the position of the sulfide ion and the way it influences the crystal structure around the vacant chalcogenide position at (0 0 0).
Confirmation by an X-ray crystallography study of a molecular modeling prediction about the coordination scheme of a new (1,4,8,11-(tetra-2-carboxyethyl)-1,4,8,11-tetraazacyclotetradecane)cerium(III) complex
Authors: Lecomte Claude , Dahaoui-Gindrey V. , Barbette F. , Pullumbi P. , Gros C.P. , Guilard R. , Dahaoui Slimane 
Published: August 2006

The synthesis and characterization of a new cerium(III) complex with the ligand 1,4,8,11-(tetra-2-carboxyethyl)-1,4,8,11-tetraazacyclotetradecane (TETP), Ce(C22N4O8H38)(NO3)(H2O)3 · 3 H2O, is described. The cerium ion is eight-coordinated, linked to four carboxyl oxygen atoms belonging to four different TETP macrocycles as well as to three solvate water molecules, and to one oxygen atom of a disordered NO3
- anion. Each asymmetric unit consists of two different half TETP ligands. Each centrosymmetric TETP macrocycle possesses a [3434] conformation, two propionate arms being extended and the others folded towards two protonated nitrogen atoms. The four functionalized chains of the ligand whatever their conformation (extended or folded) are involved in the coordination polyhedron of cerium ion. This coordination mode was predicted from Molecular Electrostatic Potential calculations which showed the more negative potential sites of the ligand where the lanthanide cation would approach and coordinate.
Crystal structures of Cd(ReO4)2 · 4Urea, Cd(ReO4)2 · 6Urea and Ca(ReO4)2 · 5Urea. Synthesis and characterization of urea adducts from the systems M(ReO4)2-Urea-H2O, M = Ca, Sr, Ba, Pb and Cd
Authors: Petrova R. , Todorov T. , Bakardjieva S. , Mihailova Boriana , Angelova O. 
Published: August 2006

The crystal structutes of Cd(ReO4)2 · 4Urea, Cd(ReO4)2 · 6Urea and Ca(ReO4)2 · 5Urea were solved. Cd(ReO4)2 · 4Urea consists of discrete neutral [Cd(ReO4)2L4] (L = Urea) clusters. Ca(ReO4)2 · 5Urea and Cd(ReO4)2 · 6Urea are built up of cationic [Ca(ReO4)L5]+ and [CdL6]2+ clusters, respectively, and ReO4- anions, interlinked by an extensive network of H-bonds. The octahedral coordination of M atoms is most regular in Cd(ReO4)2 · 6Urea and most distorted in Ca(ReO4)2 · 5Urea.
With the synthesis and X-ray analysis of these new urea adducts the investigation of the systems M(ReO4)2-Urea-H2O, M = Ca, Sr, Ba, Pb and Cd, was accomplished. This paper represents and a review of the synthesis, X-ray study and IR characterisation of the stable phases from the mentioned systems.
In situ electron diffraction study of synthetic (Ca1-xSrx)2MgSi2O7 åkermanites
Authors: Rager H. , Schosnig M. , Schaper A.K. , Kutoglu A. , Treutmann W. 
Published: August 2006

This paper deals with transmission electron microscope experiments of Ca,Sr-åkermanite solid solutions at temperatures between 100 K and 375 K. The aim of the investigations was to study the compositional and temperature dependence of phase transitions from the normal to the incommensurately modulated structure of
(Ca1-xSrx)2MgSi2O7 single crystals observed by electron diffraction. With increasing Sr-content the normal to incommensurate phase transition temperature decreases linearly from ca. 350 K (x = 0.04) to 295 K (x = 0.22). Depending on temperature and composition, the incommensurate phase is structurally not uniform, its stability field can be divided into two regions. The transition between the two regions can be recognized by the additional appearance of higher order satellite reflections in the diffraction pattern. Additionally, the transition is characterized by an abrupt change of the modulation wavelength. Within the high-temperature, low ordered region, the modulation wavelength varies between 18.5 Å and 20.5 Å, whereas no changes of the wavelength have been found in the low-temperature, higher ordering region. With increasing Sr-content the high-temperature, low ordered phase covers a steadily increasing temperature range.
Crystal structure and crystal chemistry of biehlite, Sb1.79As0.21MoO6
Authors: Adiwidjaja G. , Friese Karen , Klaska K.-H. , Schlüter J. , Czank M. 
Published: August 2006

The new mineral biehlite was found in the Tsumeb mine, Namibia and has the composition Sb1.79As0.21MoO6. It crystallizes monoclinic, space group C2/c with lattice paramters a=18.076(5)Å, b= 5.920(5)Å, c=5.083(5)Å, β= 96.97(1)°. Refinement led to a final R(F) value of 0.065 for 679 symmetrically independent reflections.
[MoO6]6- octahedra share common edges and form zigzag chains which run parallel to the c direction. The octahedra are flanked by a [Sb2O2]2+ group on each side and infinite ribbons of composition [Sb4Mo2O12] are obtained. Neighbouring ribbons are only held together by weak Sb-O bonds in the directions of a and b.
The [MoO6]6- octahedra are strongly distorted with Mo-O distances ranging from 1.700(5) to 2.248(6) Å and O-Mo-O angles between 72.1(2)° and 105,3(4)°. The common O-O edge (2.492(8)Å) is shortened with respect to the remaining edges of the octahedra (2.704(8)Å-2.899(8)Å).
The Sb-cation forms three short bonds with oxygen at distances slightly smaller than 2Å. Six further oxygen atoms are located at distances ranging from 2.910(6) to 3.470(6)Å. Calculated distance for the lone-pair is 1.18 Å. Part of the Sb3+ is substituted by the smaller As3+ ion. The relationship of the new mineral to similar structures – especially to the mineral stibivanite and the synthetic compound Sb2MoO6 – are discussed.
Comparative Studies on the Complex-Formation Equilibria of Mercury(II) with Acetylcysteine and Captopril
Authors: Köszegi-Szalai H. , Paál T.L. , Barcza L. 
Published: August 2006

The complex-formation equilibria of mercury(II) with acetylcysteine and captopril have been studied by pH-metric and liquid-liquid extraction methods applying dithizone as a competitive ligand during the latter measurements. The stability constants of three differently protonated Hg(II)/ligand 1:2 complexes of extreme stability have been determined by the combination of extraction and pH-metric data.The formation of the less stabil Hg(II)-ligand 1:3 complexes with the coordination of three sulfhydrilate groups has been followed and the values of βThe differences in the Hg(II) complex formation and protonation equilibria between the two ligands and the possible binding sites in the complexes have been discussed.
Raman Spectroscopic Studies of Scandium(III) Hydration in Aqueous Solution - about the First Hydration Sphere of Sc(III) in Solution
Authors: Rudolph W.W. 
Published: August 2006

It has been shown conclusively that Sc(III) in aqueous perchlorate solution occurs as an hexaaqua cation. The weak, polarized Raman band assigned to theBesides the polarized component at 442 cmThese findings are also in contrast to the results found in Sc
Phase Diagrams in Volume, Mole Fraction Coordinates
Authors: Lentz H. 
Published: August 2006

For a binary mixture the V,x-diagram with isotherm and isobaric curves contains the complete information about the phase behavior of the system. In ternary mixtures isotherm and isobaric surfaces and additional information on the tie lines describe the complete phase behavior.For a binary mixture the V,x-phase diagrams corresponding to the classified P,T-phase diagrams are shown. The constitute binary V,x-phase diagrams and partly the critical V,x-surfaces of the ternary systems are shown for NH
High Resolution Electron Ionization of N2O Clusters: Appearance Energies
Authors: Hanel G. , Fiegele T. , Stamatovic A. , Märk T.D. 
Published: August 2006

Electron ionization cross sections for (NComparison of the presently derived appearance energies with earlier photoionization data shows a distinct difference in corresponding values attributed to different ionization mechanisms. Both data sets can be fitted successfully by a n
NMR Study of Hydrogen Bonding Association of 2-Isopropylphenol in Carbon Tetrachloride, Acetone, Dimethyl Sulphoxide and Acetonitrile
Authors: Luo W.-C. , Lay J.-L. , Chen Jenn-Shing 
Published: August 2006

Abstract
This study investigates the association of 2-isopropylphenol through hydrogen bonding in carbon tetrachloride, [2H6]acetone, [2H3]acetonitrile and [2H6]dimethyl sulphoxide by using high resolution nuclear magnetic resonance spectroscopy. Chemical shifts of the hydroxyl proton were measured over a wide range of temperature and concentration. The chemical shift data were treated by a graphical method to determine the monomer shift, dimer shift and dimerization constant. The enthalpy and entropy of dimerization were determined via a van´t Hoff plot from the temperature variation of the dimerization constant.
Nonmetal-Metal Transition in Liquid Cu-Based Alloys
Authors: Sklyarchuk V. , Plevachuk Y. 
Published: August 2006

Abstract
Electrical conductivity σ(T) and thermo-e.m.f. S(T) measurements were performed for ternary Cu-based chalcogenides in a wide temperature range. A concentration range of the semiconductor-metal transition has been determined. A radical alteration in the electron spectrum occurs in the region of x = 0.6-0.8, namely, a semiconductor-metal transition takes place. Complete metallization of alloys takes place with temperature increasing. Further heating is accompanied by electrical conductivity decreasing followed by final exponential electrical conductivity dependence with seeming negative activation energy, while thermopower increases without changing a sign. This process is accompanied by an increase of a free electrons concentration. At the same time, at higher temperatures when the alloy’s density decreases, localization of the wave functions of electrons on separated atoms or atoms groups caused by density fluctuations, occurs. For alloys with Se content, the electrical conductivity decreasing caused by thermal expansion, could be intensified at the expense of molecular units formation. A simultaneous density decreasing causes an appearance of small dynamic groups like Se2, Se3, Se6. While similar molecular complexes appear, a very inhomogeneous in a structural and energy sense system in being formed. Peculiarities of the reverse metal-semiconductor transition were studied.
Gibt es eine Lernkurve der Forschung?
Authors: Röß D. 
Published: August 2006

Laser is an example of how new markets are created by breakthroughs in basic research. The time development of important research contributions and of product ideas is described, as well as the personal background of A. L. Schawlow, one of the pioneers in both areas. AFritz Schäfer ist einer der Pioniere des Lasergebiets. Er hat mit seinen frühen Entdeckungen zu Laserfunktion in organischen Farbstoffen neue Türen geöffnet, und über viele Jahrzehnte hinweg originelle Beiträge zur Anwendung des Lasers als Instrument der Forschung geleistet. Darüber hinaus wurde er durch sein ausgeprägtes Interesse für die praktische Umsetzung wissenschaftlicher Erkenntnisse in industrielle Tätigkeit zum Geburtshelfer bei der Gründung der Firma
Investigation of the Thermal Decomposition of Ketene and of the Reaction CH2 + H2 ⇔ CH3 + H
Authors: Friedrichs G. , Wagner H.Gg. 
Published: August 2006

Using frequency modulation (FM) spectroscopy singlet methylene radicals have been detected for the first time behind shock waves. The thermal decomposition of ketene served as source for metylene radicals at temperatures from 1905 to 2780 K and pressures around 450 mbar. For the unimolecular decomposition reaction, (1) CHAs a first study of a methylene reaction at high temperatures by diretly tracing methylene the reaction of methylene with hydrogen, (8 + 9)log(A comparison with low temperature literature data and the systematics of activation energies of triplet methylene reactions allowed a consistent description of singlet and triplet contributions and of the forward and reverse reaction.
Adsorption of Hydrogen Azide on the NaCl(100) Single Crystal Surface. Orientational and Translational Ordering of the HN3 Monolayer as Revealed by PIRS, LEED and Spectra Simulation
Authors: Heidberg J. , Hustedt M. , Oppermann H. , Paszkiewicz P. 
Published: August 2006

The adsorption of hydrogen azide HNOrdered molecular adsorption of HNIsotopic mixture experiments with H
Studies on Charge-Transfer and Hydrogen Bond Formation with Cyproheptadine
Authors: Gangopadhyay J. , Lahiri Sujit Chandra 
Published: August 2006

Cyproheptadine, an antihistaminic and antipruritic drug, forms fairly stable charge-transfer complexes with quinone (Q), chloranil (Chl-Q) and anthraquinone (AQ) in chloroform. It also forms stable hydrogen bonds with alcohols (methanol and propanol) and phenols (α-naphthol,The results suggest that cyproheptadine can form loose association with receptors through charge-transfer and hydrogen bond complex formation.
Biochemical Synthesis in Microstructured Silicon Wafer
Authors: Gebinoga Michael , Schlingloff Gregor , Beck Christine , Thamm Antje , Schober Andreas 
Published: August 2006

In biotechnics microsystems have been introduced primarily for analytical purpose in the past few years. Recently miniaturised microtiterplates, so called nanotiterplates, as efficient tools in screening have been discussed.In a case study we demonstrate the application of cell-free translation or transcription/translation and nucleic acid amplification in such nanotiterplates.The results show the potential range of applications of nanotiterplates for biotechnology even for biochemical systems, which have not been discussed as miniaturisable in screening.
The Viscosity of n-Decane to High Temperatures of 573 K and High Pressures of 300 Mpa
Authors: Naake Lutz-Dieter , Wiegand Gabriele , Franck Ernst Ulrich 
Published: August 2006

The dynamic viscosity of liquidThe viscosity increases at 373 K from 375 to 1602 μPa s in the pressure range from 0.1 to 200 MPa, at 473 K from 200 to 1114 μPa s in the pressure range from 10 to 300 MPa, and at 573 K from 223 to 675 μPa s in the pressure range from 60 to 300 MPa. The mean accuracy of the viscosity measurements is about 1.3 %. A polynomial function describing the viscosity variation with pressure and temperature is given. The maximum average deviation is 0.46 %, the mean average deviation between measured and calculated data is 0.11 %. The viscosity as a function of density is also shown. With Arrhenius plots, the energies of activation are obtained.
Intramolecular Photoinduced Electron Transfer in Zwitterionic Quinolinium Dyes – Experimental and Theoretical Studies
Authors: Engel T. , Käb G. , Lanig H. 
Published: August 2006

Quinolinium cations and quinolinium betaines were investigated in the representative solvents water and acetonitrile at room temperature using stationary and time-resolved fluorescence spectroscopy (Experimental results reveal that sulfoalkyl- and carboxyalkyl-quinolinium compounds display a strikingly different behavior in the two solvents. Furthermore, the fluorescence lifetime depends on the length of the spacer for the sulfoalkyl compounds in acetonitrile and the carboxyalkyl compounds in water, respectively. This suggests an intramolecular interaction of the anionic headgroups with the quinolinium system in the excited state. To support this idea, different positions at the chromophore are substituted by a methylgroup in order to perturb the proposed interaction.With the intention to understand the dynamics of the postulated photoinduced electron transfer from the anionic group onto the excited quinolinium chromophore, semiempirical quantum chemical calculations were performed on the species using the PM3 hamiltonian including solvent effects by a self consistent reaction field (SCRF).We show that the Marcus theory of electron transfer may serve as a theoretical basis for a natural interpretation of the dynamic fluorescence quenching behavior.
The Photolysis of Fluorine at 366 nm in the Presence of Bis(Fluoroformyl)Peroxide
Authors: Croce A.E. , Tori C. A. , Castellano E. 
Published: August 2006

The photolysis of molecular fluorine at 366 nm in the presence of bis(fluoroformyl)peroxide, (FCO)FF + FC(O)OO(O)CF → FC(O)OF + FC(O)OF (2)F + FC(O)OO(O)CF → FF + FC(O)O → FC(O)OF (4)2FF → ½FOn the other hand, Φ decreases with increasing OF + OFOF + FOThe formation of CFF + CFfollowed by a secondary mechanism, being
17β-Estradiol induces Akt-1 through estrogen receptor-β in the frog (Rana esculenta) male germ cells
Authors: Stabile Veronica , Russo Maria , Chieffi Paolo 
Published: August 2006

Several lines of evidence support the key role of estrogens in male fertility. Here, we investigate the regulation of the serine/threonine kinase Akt-1 in the frog (Rana esculenta) testis during the annual sexual cycle and, whether 17β-estradiol (E2) exerts a role in the Akt-1 activity. Akt-1 has been shown to be the mediator of growth factor-dependent cell proliferation, survival, and metabolism in a variety of cell types.
First, we demonstrate by immunohistochemistry, the presence of estrogen receptor-β (ERβ), and Akt-1 in the spermatogonia (SPG), spermatocytes (SPC), and spermatids (SPT). Western-blot analysis revealed that ERβ isoform (molecular weight 55 kDa) was highly expressed in May (reproductive period) with respect to January and November (winter stasis); in parallel, Akt-1 (molecular weight 60 kDa) is highly phosphorylated (Ser-473) during the period of active spermatogenesis (May) compared with the winter stasis (January and November). In addition, in vitro experiments demonstrate that E2 treatment induces the activation of Akt-1, and this effect is counteracted by the anti-estrogen ICI 182–780. In conclusion, our data show that E2 induces Akt-1 phosphorylation (Ser-473) possibly via ERβ in frog (R. esculenta) male germ cells.