bluuebunny/crossref_metadata_2025_split huggingface dataset:
Planung von nichttragenden Bodenplatten
Authors: Schöppel Klaus 
Published: September 2007

AbstractNichttragende Bodenplatten werden i. A. als unbedeutende Bauteile angesehen. Wie die Praxis zeigt, setzen sich die Planenden häufig weder mit den Vorstellungen des Bauherrn bezüglich seiner Bodenplatte noch deren Realisierbarkeit genau auseinander. Selten werden Sonderfachleute zur Beratung des Bauherrn, für Planung und Ausführung von Bodenplatten hinzugezogen. Der unbedachte Umgang mit dem Thema nichttragende Bodenplatten führt zwangsläufig zu Mängeln und häufig aufgrund der hohen Mängelbeseitigungskosten vor allem infolge des Nutzungsausfalls zu gerichtlichen Auseinandersetzungen.In diesem Beitrag werden daher die wesentlichen Randbedingungen und Vorgaben für eine nichttragende Bodenplatte, die bereits im frühen Planungsstadium mit dem Bauherrn abzuklären sind, aufgezeigt. Des Weiteren wird ein Überblick über die Konstruktionsmöglichkeiten nichttragender Bodenplatten gegeben. Ergänzend wird auf die Stellung von nichttragenden Bodenplatten im Regelwerk sowie auf häufig auftretende Schadensbilder eingegangen.
Prediction of The Kolmogorov Entropy Derived from CT Data in a Bubble Column Operated under The Transition Regime and Ambient Pressure
Authors: Nedeltchev S. , Shaikh A. , Al‐Dahhan M. 
Published: September 2007

AbstractThe Kolmogorov entropy (KE) algorithm was successfully applied to single source γ‐ray Computed Tomography (CT) data measured by three scintillation detectors in a 0.162 m‐ID bubble column equipped with a perforated plate distributor (163 holes × ∅︁ 1.32 · 10–3 m). The aerated liquid height was set at 1.8 m. Dried air was used as a gas phase, while Therminol LT (ρL = 886 kg m–3, μL = 0.88 · 10–3 Pa s, σ = 17 · 10–3 N m–1) was used as a liquid phase. At ambient pressure, the superficial gas velocity, uG, was increased stepwise with an increment of 0.01 m s–1 up to 0.2 m s–1. Based on the sudden changes in the KE values, the boundaries of the following five regimes were successfully identified: dispersed bubble regime (uG < 0.02 m s–1), first transition regime (0.02 ≤ uG < 0.08 m s–1), second transition regime (0.08 ≤ uG < 0.1 m s–1), coalesced bubble regime consisting of four regions (called 4‐region flow; 0.1 ≤ uG < 0.12 m s–1), and coalesced bubble regime consisting of three regions (called 3‐region flow; uG > 0.12 m s–1). The KE values derived from three scintillation detectors in the first transition regime were successfully correlated to both bubble frequency and bubble impact. The latter was found to be inversely proportional to the bubble Froude number. The KE model implies that the bubble size in this particular flow regime is a weak function of the orifice Reynolds number (db = 7.1 · 10–3Re0–0.05).
Human Factors Assessment Technique for the Chemical Process Industry
Authors: Gitahi Kariuki S. , Mayor Vadillo E. , Löwe K. 
Published: September 2007

AbstractThis paper outlines the development of a new human factors assessment tool for the chemical process industry. The approach considers the whole human factors spectrum as the basis for determining the overall quality of human factors in the plant under assessment. The output of the technique is a qualitative report and of quantitative value. From the detailed report, the weak areas in a plant can be detected. The actions to improve these areas can be derived and this not only leads to higher safety but also to higher operation efficiency. The developed computer interface makes the technique especially easy to use, even for non‐human factors experts.
The Influence of Shear Stress on Crystallization in an Ultrasound Levitator
Authors: Sacher S. , Krammer G. 
Published: September 2007

AbstractIndustrial precipitation processes often use chemical agents to influence crystal morphology and size distribution. This experimental study deals with the investigation of physical parameters including an alternative method to affect crystal growth, thus, avoiding the presence of additives as intrinsic impurities. The influence of shear stress acting on growing crystals within a droplet is investigated in an ultrasound levitator. An ultrasound levitator enables the suspension of a single droplet against gravity and the study of containerless precipitation with specific mechanical forces acting on crystals. The levitator is used as a three‐phase reactor with precipitation from the gas and liquid, and as a reactor for precipitation from two different solutions. Calcium carbonate is used as a model system. The variation of temperature and the amount of applied shear stress leads to different amounts of calcium carbonate morphologies. An increase in the shear stress results in more rounded or spherical crystals. The intensity of the shear stress also influences the particle size distributions of the precipitated crystals, i.e., with increasing shear stress, particle size distributions are shifted to smaller sizes.
Site Selectivity in the Reactions of the Hexanuclear Platinum Cluster [Pt6(μ‐PtBu2)4(CO)6][CF3SO3]2
Authors: Bonaccorsi Cristina , de Biani Fabrizia Fabrizi , Leoni Piero , Marchetti Fabio , Marchetti Lorella , Zanello Piero 
Published: September 2007

AbstractThe previously reported hexanuclear cluster [Pt6(μ‐PtBu2)4(CO)6]2+[Y]2 (1‐Y2: Y=CF3SO3−) contains a central Pt4 tetrahedron bridged at each of the opposite edges by another platinum atom; in turn, four phosphido ligands bridge the four PtPt bonds not involved in the tetrahedron, and, finally, one carbonyl ligand is terminally bonded to each metal centre. Interestingly, the two outer carbonyls are more easily substituted or attacked by nucleophiles than the inner four, which are bonded to the tetrahedron vertices. In fact, the reaction of 1‐Y2 with 1 equiv of [nBu4N]Cl or with an excess of halide salts gives the monochloride [Pt6(μ‐PtBu2)4(CO)5Cl]+[Y], 2‐Y, or the neutral dihalide derivatives [Pt6(μ‐PtBu2)4(CO)4X2] (3: X=Cl; 4: X=Br; 5: X=I). Moreover, the useful unsymmetrically substituted [Pt6(μ‐PtBu2)4(CO)4ICl] (6) was obtained by reacting equimolar amounts of 2 and [nBu4N]I, and the dicationic derivatives [Pt6(μ‐PtBu2)4(CO)4L2]2+[Y]2 (7‐Y2: L=13CO; 8‐Y2: L=CNtBu; 9‐Y2: L=PMe3) were obtained by reaction of an excess of the ligand L with 1‐Y2. Weaker nitrogen ligands were introduced by dissolving the dichloride 3 in acetonitrile or pyridyne in the presence of TlPF6 to afford [Pt6(μ‐PtBu2)4 (CO)4L2]2+[Z]2 (Z=PF6−, 10‐Z2: L=MeCN; 11‐Z2: L=Py). The “apical” carbonyls in 1‐Y2 are also prone to nucleophilic addition (Nu−: H−, MeO−) affording the acyl derivatives [Pt6(μ‐PtBu2)4(CO)4(CONu)2] (12: Nu=H; 13: Nu=OMe). Complex 12 is slowly converted into the dihydride [Pt6(μ‐PtBu2)4(CO)4H2] (14), which was more cleanly prepared by reacting 3 with NaBH4. In a unique case we observed a reaction involving also the inner carbonyls of complex 1, that is, in the reaction with a large excess of the isocyanides RNC, which form the corresponding persubstituted derivatives [Pt6(μ‐tPBu2)4(CNR)6]2+[Y]2, (15‐Y2: R=tBu; 16‐Y22−: R=−C6H4‐4‐CCH). All complexes were characterized by microanalysis, IR and multinuclear NMR spectroscopy. The crystal and molecular structures of complexes 3, 5, 6 and 9‐Y2 are also reported. From the redox viewpoint, all complexes display two reversible one‐electron reduction steps, the location of which depends both upon the electronic effects of the substituents, and the overall charge of the original complex.
Contrasting Photodynamics between C60–Dithiapyrene and C60–Pyrene Dyads
Authors: Guldi Dirk M. , Spänig Fabian , Kreher David , Perepichka Igor F. , van der Pol Cornelia , Bryce Martin R. , Ohkubo Kei , Fukuzumi Shunichi 
Published: September 2007

AbstractThe photodynamics of a C60–dithiapyrene donor–acceptor conjugate were compared with the corresponding C60–pyrene conjugate. The photoinduced charge separation and subsequent charge recombination processes were examined by time‐resolved fluorescence measurements on the picosecond timescale and transient absorption measurements on the picosecond and microsecond timescales with detection in the visible and near‐infrared regions. We have observed quite long lifetimes (i.e., up to 1.01 ns) for the photogenerated charge‐separated state in a C60–dithiapyrene dyad without the need for i) a long spacer between the two moieties, or ii) a gain in aromaticity in the radical ion pair.
Copper(II)‐Mediated Aromatic ortho‐Hydroxylation: A Hybrid DFT and Ab Initio Exploration
Authors: Comba Peter , Knoppe Stefan , Martin Bodo , Rajaraman Gopalan , Rolli Claudio , Shapiro Brett , Stork Timon 
Published: September 2007

AbstractMechanistic pathways for the aromatic hydroxylation by [CuII(L1)(TMAO)(O)]− (L1=hippuric acid, TMAO=trimethylamine N‐oxide), derived from the ON bond homolysis of its [CuII(L1)(TMAO)2] precursor, were explored by using hybrid density functional theory (B3LYP) and highly correlated ab initio methods (QCISD and CCSD). Published experimental studies suggest that the catalytic reaction is triggered by a terminal copper–oxo species, and a detailed study of electronic structures, bonding, and energetics of the corresponding electromers is presented. Two pathways, a stepwise and a concerted reaction, were considered for the hydroxylation process. The results reveal a clear preference for the concerted pathway, in which the terminal oxygen atom directly attacks the carbon atom of the benzene ring, leading to the ortho‐selectively hydroxylated product. Solvent effects were probed by using the PCM and CPCM solvation models, and the PCM model was found to perform better in the present case. Excellent agreement between the experimental and computational results was found, in particular also for changes in reactivity with derivatives of L1.
Nanosized Ball Joints Constructed from C60 and Tribenzotriquinacene Sockets: Synthesis, Component Self‐Assembly and Structural Investigations
Authors: Bredenkötter Björn , Henne Stefan , Volkmer Dirk 
Published: September 2007

AbstractThe formation of supramolecular host–guest complexes of fullerene (C60) and two novel tribenzotriquinacene based hosts (5 a and 5 b) was investigated in solution and in the solid state. Stability constants for 1:1 and 2:1 complexes were obtained from spectroscopic (UV/Vis, 1H NMR) titration experiments. Association constants of K1=(2908±360) L mol−1 and K2=(2076±300) L mol−1 for C60/5 a, and K1=(5608±220) L mol−1 and K2=(673±160) L mol−1 for C60/5 b were obtained. Single crystal X‐ray structural analysis of compound C60⊂5 b⋅3 toluene revealed that a molecule of C60 was located at short van der Waals contact distances in the open pre‐organised cavity of the rigid host. The supramolecular complex created resembles an engineered nanosized ball joint and represents the first member for a future nanomechanics construction kit.
Wirkstoffe auf Basis biologisch aktiver Naturstoffe
Authors: Heilmann Jörg 
Published: September 2007

AbstractIm Bereich der Wirkstoffsuche sind Naturstoffe unverzichtbar. Problematisch bei der Gewinnung von Naturstoffen sind die Beschaffung des biologischen Materials, die Auffindung und Isolierung aus einer inaktiven oder sogar die biologische Testung störenden Matrix und die Gewinnung ausreichender Mengen zur chemischen und pharmakologischen Charakterisierung bzw. für die klinische Nutzung. Oft stellen Naturstoffe ideale Leitstrukturen für die synthetische oder semisynthetische Entwicklung von Wirkstoffen dar. Besonders attraktiv sind Naturstoffe dann, wenn die biologische Quelle erneuerbar bzw. sogar in Kultur modifizierbar ist. Dies ist ein wesentlicher Aspekt für die gegenwärtige Attraktivität der Wirkstoffsuche in Mikroorganismen wie Bakterien und Pilzen. Diese können im Idealfall nicht nur in Fermentern kultiviert, sondern dort auch genetisch so verändert werden, dass neuartige Strukturen entstehen.
Süße Kaugummis gegen Karies
Authors: Harrer Roswitha 
Published: September 2007

AbstractLässt sich Karies durch Kaugummikauen bekämpfen? Das hängt davon ab, mit welcher Substanz das Kaugummi gesüßt ist. Enthält es anstelle der zahnschädigenden Saccharose den Zuckeralkohol Xylit als Süßungsmittel, sind deutliche antikariogene Eigenschaften nachweisbar.
Der Schwefelzyklus
Authors: Jaenicke Lothar 
Published: September 2007

AbstractDie natürlichen Rezyklisierungen von Stickstoff, Kohlenstoff, ja auch Sauerstoff sind wohlbekannt, wenn auch meist nicht verantwortlich gestützt. Aber dass auch Schwefel einem Kreislauf in der Natur vom anorganischen Meeressediment zum biologischen Molekül und zurück zum Mineral unterliegt, ist viel weniger biochemisches Allgemeingut.
Cohesin – Klebstoff für Schwesterchromatiden
Authors: Hille‐Rehfeld Annette 
Published: September 2007

AbstractVor der Teilung eukaryotischer Zellen wird die Erbinformation verdoppelt. Der kopierte DNAStrang und das Original, die als Schwesterchromatiden bezeichnet werden, bleiben bis zur Kernteilung miteinander verbunden. Wie DNA‐Schäden in Form von Doppelstrangbrüchen den Kontakt der Schwesterchromatiden beeinflussen, wurde jetzt an Hefezellen untersucht.
Synthesis of Hetero Atom Modified Pyrromethenones
Authors: Bongards Christian , Gärtner Wolfgang 
Published: September 2007

AbstractA series of six heteroaromatic compounds, ethyl‐/methyl‐ and dimethylfuranones, thiophenones, and cyclopentenones, was synthesized and condensed with a methyl methylpropionate substituted pyrrole, yielding the “right” half of open‐chain tetrapyrroles. These compounds serve as light‐inducible chromophores in the plant photoreceptor phytochrome. Three‐dimensional structure analysis of the 10‐oxapyrromethen‐1‐one 25 revealed a planar conformation, similar to the dipyrromethenone parent compound, stabilized by ahydrogen bond formed between the pyrrole proton and the furanone oxygen atom. All six pyrrole‐substituted heteroaromatic derivatives 25–30 show absorbances in the visible spectrum with high molar extinction coefficients.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Modelling raindrop impact and splash erosion processes within a spatial cell: a stochastic approach
Authors: Ma Ting , Zhou Chenghu , Zhu Tongxin , Cai Qiangguo 
Published: September 2007

AbstractA new approach is proposed to simulate splash erosion on local soil surfaces. Without the effect of wind and other raindrops, the impact of free‐falling raindrops was considered as an independent event from the stochastic viewpoint. The erosivity of a single raindrop depending on its kinetic energy was computed by an empirical relationship in which the kinetic energy was expressed as a power function of the equivalent diameter of the raindrop. An empirical linear function combining the kinetic energy and soil shear strength was used to estimate the impacted amount of soil particles by a single raindrop. Considering an ideal local soil surface with size of 1 m × 1 m, the expected number of received free‐falling raindrops with different diameters per unit time was described by the combination of the raindrop size distribution function and the terminal velocity of raindrops. The total splash amount was seen as the sum of the impact amount by all raindrops in the rainfall event. The total splash amount per unit time was subdivided into three different components, including net splash amount, single impact amount and re‐detachment amount. The re‐detachment amount was obtained by a spatial geometric probability derived using the Poisson function in which overlapped impacted areas were considered. The net splash amount was defined as the mass of soil particles collected outside the splash dish. It was estimated by another spatial geometric probability in which the average splashed distance related to the median grain size of soil and effects of other impacted soil particles and other free‐falling raindrops were considered. Splash experiments in artificial rainfall were carried out to validate the availability and accuracy of the model. Our simulated results suggested that the net splash amount and re‐detachment amount were small parts of the total splash amount. Their proportions were 0·15% and 2·6%, respectively. The comparison of simulated data with measured data showed that this model could be applied to simulate the soil‐splash process successfully and needed information of the rainfall intensity and original soil properties including initial bulk intensity, water content, median grain size and some empirical constants related to the soil surface shear strength, the raindrop size distribution function and the average splashed distance. Copyright © 2007 John Wiley & Sons, Ltd.
Spatial variability in the timing, nature and extent of channel response to typical human disturbance along the Upper Hunter River, New South Wales, Australia
Authors: Hoyle Joanna , Brooks Andrew , Brierley Gary , Fryirs Kirstie , Lander James 
Published: September 2007

AbstractPrior to European settlement, the Upper Hunter River near Muswellbrook, New South Wales, was a passively meandering gravel‐bed river of moderate sinuosity and relatively uniform channel width. Analyses of floodplain sedimentology, archival records, parish maps and aerial photographs document marked spatial variability in the pattern of channel change since European settlement in the 1820s. Different types, rates and extents of change are reported for seven zones of adjustment along an 8 km study reach. This variable adjustment reflects imposed antecedent controls (buried terrace material and bedrock), which have significantly influenced local variability in river sensitivity to change, as well as contemporary morphodynamics and geomorphic complexity. Local variability in system responses to disturbance has important implications for future river management and rehabilitation. Copyright © 2007 John Wiley & Sons, Ltd.
Climate effects on soil erodibility
Authors: Sanchis M. P. Salvador , Torri D. , Borselli L. , Poesen J. 
Published: September 2007

AbstractSoil erodibility data, calculated using measured soil loss from standard runoff plots, collected over at least one year and applying the standard requirements for calculating the soil erodibility factor (K) of the Universal Soil Loss Equation (USLE), have been analysed to investigate whether climate affects the susceptibility of soils to water erosion. In total, more than 300 K‐values extracted from the literature have been analysed. Due to the limited availability of data related to the characteristics of the soil and the location of the measuring sites, all the analysis has been carried out using only soil textural characteristics, organic matter content, rock fragment content and the some general characteristics of the climatic zone where the plots were located.The first evidence of a strong climate effect on soil erodibility is shown by the seasonal variation of mean monthly soil erodibility (Km). Using data collected in the USA and Italy an effect of mean monthly air temperature on Km could be identified. Data collected in Indonesia (where mean monthly air temperature remains fairly constant throughout the year) showed comparable variations of monthly soil erodibility. However, it was impossible to explain these variations in Km as no other data than mean monthly air temperature were available.Mean annual soil erodibility shows a clear climate effect. Soil erodibilities can be subdivided into two large groups, one corresponding to soils in cool climates (Df and Cf climate according to the Köppen–Geiger climate classification) and another to soils located in warm climates (tropical Af and Aw climates). Erodibilities of Mediterranean soils (found under Cs climate) plot among the soils found in Af and Aw climates. These subdivisions can be made for both stony and non‐stony soils. Limited data suggest that soil aggregate stability is a good predictor for explaining soil erodibility variations between different climate zones. Copyright © 2007 John Wiley & Sons, Ltd.
Long‐term safety and efficacy of long‐acting risperidone in elderly psychotic patients
Authors: Kissling Werner , Glue Per , Medori Rossella , Simpson Steve 
Published: September 2007

AbstractThis subgroup analysis of the 6‐month, open‐label Switch to Risperidone Microspheres (StoRMi) trial evaluated long‐term safety and efficacy of a direct conversion to risperidone long‐acting injectable (RLAI) in 52 elderly patients (≥65 years) with psychosis stabilized on oral or depot antipsychotic. Study outcomes included adverse events, movement disorder severity, psychiatric symptoms, functional ability, quality of life and patient satisfaction. Change in the Positive and Negative Syndrome Scale at endpoint was the primary efficacy measure. The most common dosage of RLAI used at endpoint was 25 mg every 14 days (60%). The trial was completed by 81% of patients, with six patients discontinuing treatment due to an adverse event. Tolerability was good and most side effects were mild to moderate. Serious adverse events occurred in 11 patients. Two of these (suicidal attempt, n = 1; exacerbation of disease, n = 1) were considered possibly related to RLAI. Conversion to RLAI resulted in significant improvements in movement disorder severity, psychiatric symptoms, functional status and patient satisfaction. Mean PANSS total decreased by 15.8 at endpoint, with 23 patients (46.9%) experiencing a ≥20% improvement. This post‐hoc analysis supports that RLAI is well tolerated and safe in elderly patients with psychotic illnesses switched from stable antipsychotic regimens, and suggests possible efficacy, although inferences are limited. Copyright © 2007 John Wiley & Sons, Ltd.
Imaging of blood plasma coagulation and its propagation at surfaces
Authors: Faxälv Lars , Tengvall Pentti , Lindahl Tomas L. 
Published: September 2007

AbstractA new method utilizing image capture and processing was developed for the analysis of blood plasma coagulation at surfaces. The coagulation was detected in a cuvette by time‐lapse image capture of light scattering from the developing fibrin network. By image processing and computer analysis of the captured image data, both early detection of coagulation at the surface and the propagation phase of coagulation could be measured in the same experiment. It is possible to use both platelet‐rich plasma (PRP) and platelet‐free plasma (PFP) with the method, and thereby study the platelet contribution to both surface coagulation and propagation of coagulation. Two well‐known model surfaces, hydrophilic and hydrophobic glass, were used in combination with PRP and PFP to illustrate the method. Hydrophilic glass activated coagulation significantly faster (PRP: 7.0 ± 1.7 min, PFP: 5.9 ± 1.2 min, n= 16) than hydrophobic glass (PRP: 50 ± 14 min, PFP: 65 ± 32 min, n = 16) in both PRP and PFP. Hydrophilic surfaces showed a faster initial propagation of coagulation adjacent to the surface (mean velocity: 0.14 ± 0.05 mm/ minute) compared with the propagation observed further out from the surface (mean velocity: 0.05 ± 0.01 mm/min). The method is very flexible and can be suitable for screening hemocompatibility of biomaterials. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008