bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hochwasserschäden am Schürmannbau Teil 4 / Instandsetzung der Untergeschosse
Authors: Eibl J. , Ruckenbrod C. , Löffler M. , Achermann M. , Schmid Ch. 
Published: April 2013

AbstractIm Zuge der neuen Nutzung als Funkhaus mußten u. a. die Untergeschosse instandgesetzt werden. Neben einer Sanierung der geschädigten Weißen Wanne durch umfangreiche Rißverpressung mußten auch tragende Stahlbetonbauteile saniert oder ersetzt werden. Insbesondere mußte eine neue Bodenplatte als Aufbeton kraftschlüssig mit den aufgehenden Traggliedern angeschlossen werden.
Optimierungsmethoden zur Biegebemessung von Stahlbetonquerschnitten
Authors: Mark P. 
Published: April 2013

AbstractDie Biegebemessung beliebig geformter Querschnitte unter schiefer Biegung mit Normalkraft wird als Optimierungsaufgabe formuliert, um die minimal erforderlichen Bewehrungsmengen zu ermitteln. Die Aufgabe wird mit üblichen Tabellenkalkulationsprogrammen gelöst. Beispiele und Hinweise zeigen Anwendungsmöglichkeiten und geeignete Randbedingungen.
Nichtlineares Berechnen stabförmiger Bauteile
Authors: Pfeiffer U. , Quast U. 
Published: April 2013

AbstractDie übliche lineare Berechnung der Schnittgröße und die Bemessung mit mäßiger Umlagerung reicht immer dann aus, wenn die Schnittgrößen nicht von der absoluten Größe der Verformungen oder den bei ihrer Behinderung entstehenden Zwangswirkungen abhängen. Nichtlineare Berechnungen sind nur programmgestützt sinnvoll. Es werden Rechengrundlagen, einige Regelungen in DIN 1045‐1, das Bauteilverhalten und einige Hinweise zu Ergebnissen beschrieben.
Verstärkung turmartiger Bauwerke. Typische Schwächungen und ihre Behebung
Authors: Noakowski P. , Breddermann M. , Harling A. , Rost M. , Potratz S. , Leszinski H. 
Published: April 2013

AbstractBestehende turmartige Bauwerken, wie Industrieschornsteine, Maste, Funktürme und alte, oft stillgelegte Schornsteine, die im Zeitalter des Mobilfunks z.B. als Antennenträger dienen, erfordern oftmals Verstärkungen. Der Beitrag beschreibt einige Verstärkungsmethoden von Betontürmen, Mauerwerktürmen und Betonmasten. Die dargestellten Verstärkungsmaßnahmen beziehen sich auf Standorte im Mobilfunk‐ und im reinen Industriebau.
Kompaktstützen aus Hochfestem Beton: Konstruktion und Bemessung
Authors: Mühlbauer S. , Stenzel G. 
Published: April 2013

AbstractDie Entwicklung und Anwendung von hochfestem Beton in Deutschland ist weit fortgeschritten. Für Entwurf und Bemessung stehen ausreichende Hilfsmittel zur Verfügung. Allerdings bestehen bei den bauausführenden Unternehmen noch Vorbehalte wegen der begrenzten Verarbeitungszeit des Frischbetons und der hohen Empfindlichkeit gegenüber Streuungen der Betonausgangsstoffe. Deshalb ist eine Herstellung unter den kontrollierten Bedingungen eines Fertigteilwerks, wie z. B. beim Bauvorhaben Herriot's in Frankfurt, wünschenswert. Um die dadurch erforderlichen Anschlußdetails wirtschaftlich zu lösen, hat die WALTER BAU‐AG u. a. den DYWIDAG‐Kompaktknoten entwickelt. Der Beitrag beschreibt die Weiterentwicklung dieses Stützen‐Decken‐Knotens zur Kompaktstütze, um so dem hochfesten Beton ein breites Anwendungsgebiet auch im Bereich von üblichen Hochbauten zu eröffnen.
Kopfbolzen in abgesetzten Auflagern
Authors: Herzinger R. , Elbadry M. M. 
Published: April 2013

AbstractStahlbetonbalken werden oft mit reduzierter Querschnittshöhe am Balkenende ausgebildet. Der Beitrag zeigt, daß Einzel‐ und Doppelkopfstäbe hier als Bewehrung sehr wirkungsvoll sind. Kopfbolzendübel reduzieren das Problem hoher Bewehrungskonzentrationen in den Auflagerbereichen, was das Einlegen der Bewehrungsstäbe und das Betonieren und Verdichten des Betons vereinfacht.
Querkraftbemessung von Leichtbetonbauteilen mit Querkraftbewehrung
Authors: Keller Ch. , Tue N. V. , König G. 
Published: April 2013

AbstractBei der Querkraftbemessung nach DIN 1045‐1 wird ein Fachwerkmodell mit veränderlicher Druckstrebenneigung zugrundegelegt und damit zusätzlich zur reinen Fachwerktragwirkung eine Querkraftabtragung durch Rißreibung angesetzt. Der verringerten Rißreibungskapazität von Leichtbeton wird in DIN 1045‐1 u. a. durch Erhöhung der Mindestdruckstrebenneigung Rechnung getragen. Es findet sich jedoch kein Hinweis auf die daraus resultierenden Konsequenzen für die Mindestquerkraftbewehrung. Aus Sicht der Autoren erscheinen im bezug auf die Mindestquerkraftbewehrung Nachbesserungen der DIN 1045‐1 für angebracht.
Flüssigkeitserosion und Hydroabrasivverschleiß von Stahlfaserbeton
Authors: Hu X. , Momber A. W. , Yin Y. 
Published: April 2013

AbstractEs wird der Verschleiß unbewehrter und mit Stahlfasern verstärkter Betone unter der Einwirkung schnell fließender Strömungen untersucht. Dabei zeigt sich, daß der Anströmwinkel der Strömung die Mechanismen des Werkstoffabtrages bestimmt. Der Einfluß der Strömungsgeschwindigkeit auf die Verschleißrate wird in allgemeiner Form dargestellt. Eine geringe Bewehrung mit Stahlfasern (5 kg/m�) erhöht den Verschleißwiderstand von Betonen nicht oder nicht wesentlich, wenn die Proben im rechten Winkel zu einer mit ‐vergleichsweise hohen Geschwindigkeit fließenden Strömung angeordnet sind.
Methoden zur Gütebewertung von ZfPBau‐Verfahren
Authors: Taffe Alexander , Feistkorn Sascha 
Published: April 2013

AbstractDamit aus Ergebnissen zerstörungsfreier Prüfverfahren im Bauwesen (ZfPBau‐Verfahren) zuverlässige Schlussfolgerungen gezogen werden können, ist es wichtig, die Güte der Ergebnisse zu kennen. In diesem Beitrag wird anhand von Beispielen gezeigt, wie für quantitative Messergebnisse die Messunsicherheit auf der Grundlage des GUM (Guide to the Expression of Uncertainty in Measurements) bestimmt werden kann. Für qualitative Prüfaufgaben, z.B. ob ein Objekt oder Fehler vorhanden ist oder nicht, wird die Ermittlung der POD (Probability of Detection) erläutert, die in der klassischen ZfP bereits seit längerem etabliert ist. Am Beispiel einer Spannbetonbrücke werden mögliche Prüfaufgaben benannt und exemplarisch behandelt, um den Nutzen der Ermittlung der Messunsicherheit nach GUM und der Ermittlung der Zuverlässigkeit mit der POD im Hinblick auf probabilistische Nachrechnungen von Brückenbauwerken aufzuzeigen.Methods for the evaluation of quality of non‐destructive testing methodsTo draw reliable conclusions from results gained with non‐destructive testing methods in civil‐engineering (NDT‐CE) it is important to know about the quality of results. This paper presents a methodology for quantitative (metric) testing problems to determine the uncertainty of measurement on the basis of the Guide (Guide to the Expression of Uncertainty in Measurements – GUM). For qualitative testing problems – stating the existence of a defect or not – the well‐established procedure to estimate POD parameters (Probability of Detection) according to MIL‐HDBK‐1823A is described. For both methodologies – GUM and POD – examples that may occur at prestressed concrete bridges are presented in the context of static calculations of existing bridges based on stochastic models.
Ergebnisse von Brandversuchen zur Beurteilung der schadensmindernden Wirkung von Wassernebel‐Brandbekämpfungsanlagen
Authors: Leucker Roland , Leismann Frank 
Published: April 2013

AbstractIm Rahmen des Projektes SOLIT2 wurde anhand von über 30 Großbrandversuchen im Mai/Juni 2011 die Wirksamkeit von Wassernebel‐Brandbekämpfungsanlagen in Verbindung mit der Brandlüftung in Straßentunneln erprobt. Im Maßstab 1:1 wurden dabei je zur Hälfte Flüssigkeitsbrände (“Poolfires”) mit Brandlasten zwischen 30 MW und 100 MW sowie Feststoffbrände mit kompletten LKW‐Ladungen (Brandlast 100 MW, bestehend aus Holzpaletten) ausgeführt. Neben der Überprüfung der Wirksamkeit waren die Wechselwirkungen zwischen Wassernebel‐Brandbekämpfungsanlagen und anderen Sicherheitseinrichtungen in Tunneln von besonderem Interesse, um mithilfe eines ganzheitlichen Sicherheitskonzeptes mögliche Einsparpotenziale identifizieren und praxisgerechte Lösungen entwickeln zu können. Vor dem Hintergrund der steigenden Relevanz des vorbeugenden Brandschutzes in Tunneln erfolgt in der vorliegenden Veröffentlichung eine Auswertung ausgewählter Versuchsdaten hinsichtlich der Wirkung von Wassernebel‐Brandbekämpfungsanlagen auf eine Verminderung von Bauwerksschäden.Results of Fire Tests to assess the mitigating effect of Water Mist Fire Fighting SystemsWithin the scope of the SOLIT2 project, the efficiency of water mist fire fighting systems in conjunction with fire ventilation in road tunnels was determined based on more than 30 major fire tests in May/June 2011. On a 1:1 scale, half of these tests were executed as pool fires with fire loads ranging from 30 to 100 MW and the other half as solid matter fires with complete lorry loads (fire load 100 MW – consisting of wooden pallets). Apart from checking the efficiency, the interaction between water mist fire fighting systems and other safety facilities in tunnels was of particular interest, with the aim of identifying possible savings potentials and developing practice‐oriented solutions based on a holistic safety concept. Against the background of increasing relevance for preventive fire protection in tunnels in the present article an evaluation of selected experimental data on the effect of water mist fire fighting systems to reduce concrete damage is shown.
Evaluation of biodegradable paclitaxel-eluting nanofibre-covered metal stents for the treatment of benign cardia stricture in an experimental model
Authors: Zhu Y-Q , Cui W-G , Cheng Y-S , Chang J , Chen N-W , Yan L 
Published: April 2013

Abstract

Background
Benign strictures at the cardia are troublesome for patients and often require repeated endoscopic treatments. Paclitaxel can reduce fibrosis. This study evaluated a biodegradable paclitaxel-eluting nanofibre-covered metal stent for the treatment of benign cardia stricture in vitro and in vivo.

Methods
Drug release was investigated in vitro at pH 7·4 and 4·0. Eighty dogs were divided randomly into four groups (each n = 20): controls (no stent), bare stent (retained for 1 week), and two drug-eluting stent (DES) groups with retention for either 1 week (DES-1w) or 4 weeks (DES-4w). Lower oesophageal sphincter pressure (LOSP) and 5-min barium height (5-mBH) were assessed before, immediately after stent deployment, at 1 week, and 1, 3 and 6 months later. Five dogs in each group were killed for histological examination at each follow-up point.

Results
Stent migration rates were similar (0 bare stent versus 2 DES; P = 0·548). The percentage and amount of paclitaxel released in vitro was higher at pH 4·0 than at pH 7·4. After 6 months, LOSP and 5-mBH were both improved in the DES-1w (P = 0·004 and P = 0·049) and DES-4w (both P &lt; 0·001) groups compared with the bare-stent group, with better relief when the stent was retained for 4 weeks (P = 0·004 and P = 0·007). The DES was associated with a reduced peak inflammatory reaction and less scar formation compared with bare stents, especially when inserted for 4 weeks.

Conclusion
The DES was more effective for the treatment of benign cardia stricture than bare stents in a canine model. Retention of the DES for 4 weeks led to a better clinical and pathological outcome than 1 week.
A balancing act of the brain: activations and deactivations driven by cognitive load
Authors: Arsalidou Marie , Pascual‐Leone Juan , Johnson Janice , Morris Drew , Taylor Margot J. 
Published: April 2013

AbstractThe majority of neuroimaging studies focus on brain activity during performance of cognitive tasks; however, some studies focus on brain areas that activate in the absence of a task. Despite the surge of research comparing these contrasted areas of brain function, their interrelation is not well understood. We systematically manipulated cognitive load in a working memory task to examine concurrently the relation between activity elicited by the task versus activity during control conditions. We presented adults with six levels of task demand, and compared those with three conditions without a task. Using whole‐brain analysis, we found positive linear relations between cortical activity and task difficulty in areas including middle frontal gyrus and dorsal cingulate; negative linear relations were found in medial frontal gyrus and posterior cingulate. These findings demonstrated balancing of activation patterns between two mental processes, which were both modulated by task difficulty. Frontal areas followed a graded pattern more closely than other regions. These data also showed that working memory has limited capacity in adults: an upper bound of seven items and a lower bound of four items. Overall, working memory and default‐mode processes, when studied concurrently, reveal mutually competing activation patterns.
Redesign of a Phenylalanine Aminomutase into a Phenylalanine Ammonia Lyase
Authors: Bartsch Sebastian , Wybenga Gjalt G. , Jansen Maaike , Heberling Matthew M. , Wu Bian , Dijkstra Bauke W. , Janssen Dick B. 
Published: April 2013

AbstractAn aminomutase, naturally catalyzing the interconversion of (S)‐α‐phenylalanine and (R)‐β‐phenylalanine, was converted into an ammonia lyase catalyzing the nonoxidative deamination of phenylalanine to cinnamic acid by a rational single‐point mutation. It could be shown by crystal structures and kinetic data that the flexibility of the lid that covers the active site decides whether the enzyme acts as a lyase or a mutase. An Arg92Ser mutation destabilized the closed conformation of the lid structure and converted the mutase into a lyase that exhibited up to 44‐fold increased reaction rates in the enantioselective deamination of (R)‐β‐phenylalanine. In addition, the amination rates of cinnamic acid yielding optically pure (S)‐α‐ and (R)‐β‐phenylalanine were doubled. The applicability of the mutant enzyme for kinetic resolution and asymmetric amination could be shown by biocatalysis on a preparative scale.
Campher
Authors: Steinke Katrin , Jose Elena , Siehl Hans‐Ullrich , Zeller Klaus‐Peter , Berger Stefan 
Published: April 2013

AbstractCampher wurde aus dem Wasserdampfdestillat des Campherbaums durch fraktionierte Destillation isoliert und aus Ethanol umkristallisiert. Die UV‐, CD‐, IR‐ NMR‐ und MS‐Spektren sind vollständig in den supporting informations unter www.chiuz.de wiedergegeben. Die NMR‐ sowie die Massenspektren werden eingehend interpretiert und mit theoretischen Berechnungen der 13C chemischen Verschiebungen verglichen. Das Projekt stellt eine Fortsetzung des Buches “Classics in Spectroscopy” von S. Berger und D. Sicker (Wiley‐VCH 2009) dar.
Biomimetische Oxidationen
Authors: Jaenicke Lothar 
Published: April 2013

AbstractBiomimese ist die Nachahmung von Lebensvorgängen, sei es physikalisch, chemisch oder physiologisch. Sie ist immer erstrebenswert, weil die Natur aus ihrer äonenlangen Erfahrung, in und mit der Umwelt zu überleben, meist “das Beste daraus gemacht hat”, also: Nachhaltigkeit, Schonung der Ressourcen, Rezyklisierung, Umweltfreundlichkeit, Auskommen mit den Gegebenheiten von Luft, Wasser und Mineralien, wenig wirklich nutzloser Abfall; alles was heute in der Gesellschaft propagiert (und selten realisiert) wird. Aber die Chemiker geben sich Mühe, wieder Image zu gewinnen, indem sie von den grobschlächtigen Verfahren der hemdsärmeligen Pioniere ins Bio(techno)logische – oder Biomimetische gehen.
Removal of Hydrogen Sulfide by Physico‐Biological Filter Using Mixed Rice Husk Silica and Dried Activated Sludge
Authors: Mehdinia Seyed Mahmoud , Latif Puziah Abdul , Taghipour Hassan 
Published: April 2013

AbstractThis study investigated the effectiveness of a new packing material, namely mixed rice husk silica with dried activated sludge for removing H2S. Dried sewage sludge was collected from Putrajaya sewage treatment plant in Malaysia. Rice husk silica was prepared at temperature of 800°C, after acid leaching and mixed with dried sewage sludge to be utilized in a polyvinyl chloride filter. The system was operated under variable conditions of two parameters, different inlet gas concentration and different inlet flow rate. H2S was passed through the filter with one liter of the packing material. More than 99.96% removal efficiency (RE) with empty bed residence time (EBRT) of 90–45 s and 300 ppm inlet concentration was observed. However, the RE decreased to 96.87% with the EBRT of 30 s. The maximum elimination capacity (EC) of 52.32 g/m3/h was obtained with the RE of 96.87% and H2S mass loading rate of 54 g/m3/h, while at the RE of 99.96%, maximum EC was 26.99 g/m3/h with the H2S mass‐loading rate of 27 g/m3/h. A strong significant correlation between increasing of H2S mass loading rate and pressure drop was also detected (p < 0.01). Maximum pressure drop was 3.0 mm H2O after 53 days of operating time, the EBRT of 30 s, and 54 g/m3/h of H2S loading rate. These observations suggest that the mixture of rice husk silica with dried activated sludge is a suitable physico‐biological filter for H2S removal.
Dispersion of Graphene Sheets in Aqueous Solution by Oligodeoxynucleotides
Authors: Liang Li‐Jun , Wu Tao , Kang Yu , Wang Qi 
Published: April 2013

AbstractApplications of graphene sheets in the fields of biosensors and biomedical devices are limited by their insolubility in water. Consequently, understanding the dispersion mechanism of graphene in water and exploring an effective way to prepare stable dispersions of graphene sheets in water is of vital importance for their application in biomaterials, biosensors, biomedical devices, and drug delivery. Herein, a method for stable dispersion of graphene sheets in water by single‐stranded oligodeoxynucleotides (ssODNs) is studied. Owing to van der Waals interactions between graphene sheets, they undergo layer‐to‐layer (LtL) aggregation in water. Molecular dynamics simulations show that, by disrupting van der Waals interaction of graphene sheets with ssODNs, LtL aggregation of graphene sheets is prevented, and water molecules can be distributed stably between graphene sheets. Thus, graphene sheets are dispersed stably in water in the presence of ssODNs. The effects of size and molarity of ssODNs and noncovalent modification of graphene sheets are also discussed.
Chieftaincy‐Based Community Dispute Resolution: The Case of Sierra Leone
Authors: McIntyre Miller Whitney 
Published: April 2013

AbstractSierra Leone suffered a destructive 11‐year civil war that largely left its communities torn apart and in need of vast redevelopment. One of the ways that communities are rebuilding and making efforts to move forward is through the chieftaincy‐based community dispute resolution process. Based on historical norms, this process involves the community leader, or chief, helping to resolve disputes within the community. This article reviews this chieftaincy‐based community dispute resolution process, discusses the types of disputes settled, and provides broader lessons learned for communities who may be interested in truly community‐based dispute resolution.
Linkages between Corporate Sustainability Reporting and Public Policy
Authors: Beare Dan , Buslovich Ruvena , Searcy Cory 
Published: April 2013

ABSTRACTThe purpose of this paper is to explore the linkages between corporate sustainability reporting and public policy. Interviews with experts from 35 different Canadian corporations that produce a sustainability report were held to address this issue. The interviews specifically focused on exploring how public policy influences sustainability reporting, investigating how corporate sustainability reporting influences public policy, and identifying the barriers to linking sustainability reporting with public policy. The majority of participants explained that their corporation's sustainability reporting has not been heavily influenced by public policy. Even in the relatively few cases where the participating corporations were required to report on sustainability‐related information (i.e. financial and insurance companies), there was little indication that public policy was strongly considered in reporting. Although several participants felt that their sustainability reports could or should influence public policy, there were also indications that corporations are looking for additional guidance on reporting from government. In fact, the lack of direction from government was cited as a key barrier to improved linkages between corporate sustainability reporting and public policy. Future research should focus on addressing this problem, particularly at the individual sector level. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment
AlMe3‐Mediated Regio‐ and Chemoselective Reactions of Indole with Carbamoyl Electrophiles
Authors: Velavan A. , Sumathi S. , Balasubramanian K. K. 
Published: April 2013

AbstractHerein, we report the regio‐ and chemoselective reactions of indole with carbamoyl electrophiles in presence of AlMe3. Indole‐3‐carboxamide was prepared in one‐step from a reaction of indole with tertiary carbamoylimidazole in the presence AlMe3. Under conditions for the formation of an aluminium ate complex, the reaction was diverted to the indole nitrogen. Secondary carbamoyl electrophiles in the presence of AlMe3 regiospecifically yielded trisubstituted ureas. The regiospecificity and chemoselectivity of the indole nitrogen towards ester and tertiary carbamoylimidazole functionalities were also studied.
Development of Amperometric Glucose Biosensor Based on Reconstitution of Glucose Oxidase on Polymeric 3‐Aminophenyl Boronic Acid Monolayer
Authors: Şenel Mehmet , Nergiz Cevdet , Dervisevic Muamer , Çevik Emre 
Published: April 2013

AbstractAn amperometric biosensor for determining glucose based on deflavination of the enzyme glucose oxidase and subsequent reconstitution of the apo‐protein with a complexed flavin adenine dinucleotide (FAD) monolayer is described. The GOx‐reconstituted electrode exhibited excellent electrocatalytic activities towards the reduction and oxidation of hydrogen peroxide as well. The prepared biosensor showed an excellent performance for glucose at +0.5 V with a high sensitivity (5.94 μA/mM) and relatively good response time (∼12 s) in a wide concentration range of 1–17 mM (correlation coefficient of 0.9998). The applicability to blood analysis was also evaluated.
Elimination half-life as a metric for the bioaccumulation potential of chemicals in aquatic and terrestrial food chains
Authors: Goss Kai-Uwe , Brown Trevor N. , Endo Satoshi 
Published: April 2013

Abstract

The assessment of chemicals as bioaccumulative in the regulatory process makes use of the bioconcentration factor as a metric. However, this metric does not account for the dietary uptake route and therefore cannot be applied to terrestrial food chains. In recent years, the biomagnification factor (BMF) and the trophic magnification factor (TMF) have been suggested as standard metrics for bioaccumulation. For regulatory purposes, though, the BMF and the TMF also suffer from a number of shortcomings. They are not applicable to assess uptake routes other than the diet (e.g., dermal uptake, as is important for personal care products). When measured in the field, they depend largely on biological and ecological factors and less so on the chemical's properties, and they are difficult to normalize and standardize. In the present study, the authors suggest the elimination half-life (EL0.5) of a chemical as an alternative metric for bioaccumulation. The EL0.5 is equivalent to the depuration rate constant (k2) that is measured in various bioaccumulation and bioconcentration tests. This metric can be applied to air- and water-breathing animals, and it is valuable for all uptake routes. It has a number of practical advantages over the BMF and the TMF. In combination with a standard uptake scenario, the EL0.5 can also be linked directly to a BMF threshold of unity. Thus, the EL0.5 as a bioaccumulation metric overcomes the shortcomings of the BMF and the TMF while still conserving the advantages of the latter metrics. Environ Toxicol Chem 2013;32:1663–1671. © 2013 SETAC