bluuebunny/crossref_metadata_2025_split huggingface dataset:
Windenergieanlagen: Planungsablauf am Beispiel einer Anlage mit Savoniusrotor
Authors: Beecken Christoph A. , Knull Björn 
Published: May 2011

AbstractDurch die finanzielle Förderung von Windenergieanlagen (WEA) als politisch gewünschte regenerative Energiequelle und die damit einhergehende technische Fortentwicklung hat die Windenergie eine große Bedeutung bei der Stromversorgung gewonnen. Aufgrund ihrer landschaftsprägenden Dimension spielt bei der Planung von WEA die Genehmigungsfähigkeit eine bedeutende Rolle. In diesen Themenkreis fällt auch die statische (und damit wirtschaftliche) Optimierung solcher Anlagen im Sinne einer möglichst hohen Ausnutzung der Baumaterialien. Da ein Großteil der WEA in Kleinserien hergestellt wird, ist eine Zertifizierung oder Typenprüfung vorteilhaft. Anhand einer WEA mit “Savoniusrotor” werden die Vorgehensweise bei der statischen Bemessung aufgezeigt und die wichtigsten Lastannahmen getroffen, ergänzt durch einen Ausblick auf die erforderlichen Nachweise.Wind power plants: Planning procedure using the example of a system with savonius rotor. Wind energy gained in importance for electric power supply due to financial incentives for wind turbine generators (WTG) as politically favoured renewable energy source and the resulting technical further development. Building a relevant landscape element, the approvability of the structure plays a decisive role in planning and design of WTG. Another topic is the structural (and the related economical) optimisation of the plants in terms of most effective exploitation of the building material. As most of the WTG are fabricated in small batch series, certification or type testing is advantageous. Using the example of a WTG with savonius rotor, the proceeding of the structural analysis is shown including the most important load assumptions and an outlook on the required verifications.
Sandwichfassaden aus Textilbeton — experimentelle Untersuchungen
Authors: Horstmann Michael , Hegger Josef 
Published: May 2011

AbstractDie Anforderungen an Tragfähigkeit, Verformungen und Rissefreiheit begrenzen die ausführbare Biegeschlankheit großformatiger Vorhangfassaden aus Textilbeton und erfordern monolithische oder metallische Aussteifungen. Ausreichend steife, tragfähige und dennoch leichte Querschnitte lassen sich mit Sandwichkonstruktionen realisieren, die zudem im Sinne der integralen Bauweise zusätzliche Funktionen in einem kompakten Querschnitt bündeln. Der Beitrag berichtet über die im Rahmen des Transferprojekts T03 des SFB 532 durchgeführten experimentellen Untersuchungen zum Tragverhalten von Sandwichquerschnitten unter Variation der Verbundmittel, der Dämmstoffe und der Betonschichtdicken unter Zug‐, Schub‐ und Biegebeanspruchung.Sandwich façades made of Textile Reinforced Concrete — Experimental investigations. The demands on the load‐bearing capacity and serviceability are limiting the applicable slenderness of large‐sized ventilated façades made of Textile Reinforced Concrete (TRC) and thus monolithic or metallic bracings are required. Stiff, light‐weight and at the same time capable sections can be realized with sandwich constructions that additionally offer structural‐physical functions within a compact section. This contribution reports on the experimental investigations within the transfer project T03 of SFB 532 on the load‐bearing capacity of sandwich sections with varying connectors, foam cores and thicknesses of the facings subjected to tensile, shear and bending forces.
Removing the Center from Computing: Biology's New Mode of Digital Knowledge Production
Authors: November Joseph 
Published: May 2011

AbstractWie das Rechenzentrum aus der Datenverarbeitung verschwand: Die neue Form digitaler Wissensproduktion in der Biologie. Dieser Beitrag schildert die Rolle der “National Institutes of Health” (NIH) der USA bei der Ermöglichung eines grundlegenden Wandels in der Nutzung von Computern für die Wissensproduktion und in ihrem Design als Folge ihrer Bemühungen in den frühen 1960er Jahren, Informationstechnologie auch Biologen nahezubringen. Seit 1960 versuchten die NIH die Lebenswissenschaften dadurch zu reformieren, dass sie die Forscher ermutigten, elektronische Datenverarbeitung zu nutzen. Doch trotz großzügiger Unterstützung durch Bundesmittel wurde die neue Technologie von Biologen nicht recht angenommen. Anfänglich wurde dafür der Mangel an geeigneten (d. h. digitalen) biologischen Daten, die für elektronische Verarbeitung in Computern in Frage gekommen wären, verantwortlich gemacht. Als jedoch die NIH den MIT Computerarchitekten Wesley Clark in dieser Frage konsultierten, argumentierte dieser, dass die zentralisierte Aufstellung der Rechner eine größere Herausforderung für potentielle Nutzer aus der Biologie darstelle als der Bedarf an digitalen Daten selbst. Clark überzeugte die NIH, dass sie die experimentellen und institutionellen Bedürfnisse der Biologen durch Rechenkapazitäten außerhalb von Rechenzentren befriedigen müssten, sollte eine effektive Computerisierung der Biologie gelingen. Mit Unterstützung der NIH entwickelte Clark dafür 1963 den “Laboratory Instrument Computer” (LINC), einen kleinen, interaktiven Echtzeitrechner, der für die Nutzung innerhalb des Labors und vollständige Kontrolle durch Nutzer aus der Biologie gedacht war. Einmal zur Serienreife gelangt, bildete der LINC eine praktikable Alternative zu den in den 1960er Jahren üblichen Großrechnern, die in Rechenzentren aufgestellt waren. Dadurch wurde der LINC nicht nur unter Biologen populär, sondern in den folgenden Jahrzehnten zu einem bedeutenden Vorläufer für die heutigen Rechennormen in den Naturwissenschaften und darüber hinaus den Personal Computer.
The lymphatic system: A historical perspective
Authors: Loukas Marios , Bellary Sharath S. , Kuklinski Michael , Ferrauiola Julie , Yadav Abha , Shoja Mohammadali M. , Shaffer Kitt , Tubbs R. Shane 
Published: May 2011

AbstractThe study of the lymphatic system has a lengthy history, with many notable medical minds making important contributions. We now appreciate that this system is an essential component of the immune system, as well as vital to the maintenance of fluid homeostasis within the body. A good knowledge of the lymphatic system is clinically important concerning cancer, edema, surgery, and the immune response. This article reviews the history of the evolution and discovery of the lymphatic system. Clin. Anat. 24:807–816, 2011. © 2011 Wiley‐Liss, Inc
Evaluation of the safe zone for percutaneous Kirschner‐wire placement in the distal radius: Cadaveric study
Authors: Korcek L. , Wongworawat M. 
Published: May 2011

AbstractDistal radius fractures are a common injury that is often reduced with percutaneous K‐wires. The sensory nerves in this area are at risk of injuring from pin placement. Cadaveric studies of the nerve distribution patterns have elucidated certain safe zones for pin placement that limits the risk of sensory nerve injury. These studies have advocated a limited open technique that involves a shallow incision followed by blunt dissection to the bone before a k‐wire is drilled into the radius. A previously identified safe zone in the anatomical snuffbox was evaluated in 40 cadaver wrists for k‐wire placement via a percutaneous technique that involves putting the pin directly through the skin without an incision or blunt dissection. After k‐wire placement each wrist was dissected and sensory nerve distribution relative to the pin placement was evaluated. The variability of the distribution of the sensory nerves, namely the lateral antebracheal cutaneous nerve and the superficial branch of the radial nerve, is such that no truly safe zone exists for pin placement with the percutaneous technique in this area. Clin. Anat. 24:1005–1009, 2011. © 2011 Wiley Periodicals, Inc.
Synthesis of Nanocrystalline Hydroxyapatite Nanorods via Hydrothermal Conditions
Authors: Manafi S. , Rahimipour M. R. 
Published: May 2011

AbstractThe effect of Ca(NO3)2·4H2O and (NH4)2HPO4 primary solutions as the starting materials in the synthesis of a calcium phosphate phase was examined. Therefore, wet chemical reactions were investigated in solution at different temperatures by hydrothermal conditions aimed at hydroxyapatite (Ca10(PO4)6(OH)2, HAp) synthesis. The powders were investigated by XRD, SEM, FE‐TEM, HRTEM, EDAX, SAED, and FTIR. It is found that the HAp have diameters of 25–50 nm and lengths of 120�30 nm with different morphologies. As a matter of fact, the hydrothermal method guarantees the production of HAp for different applications.
Modulated Synthesis of Zr‐Based Metal–Organic Frameworks: From Nano to Single Crystals
Authors: Schaate Andreas , Roy Pascal , Godt Adelheid , Lippke Jann , Waltz Florian , Wiebcke Michael , Behrens Peter 
Published: May 2011

AbstractWe present an investigation on the influence of benzoic acid, acetic acid, and water on the syntheses of the Zr‐based metal–organic frameworks Zr–bdc (UiO‐66), Zr–bdc–NH2 (UiO‐66–NH2), Zr–bpdc (UiO‐67), and Zr–tpdc–NH2 (UiO‐68–NH2) (H2bdc: terephthalic acid, H2bpdc: biphenyl‐4,4′‐dicarboxylic acid, H2tpdc: terphenyl‐4,4′′‐dicarboxylic acid). By varying the amount of benzoic or acetic acid, the synthesis of Zr–bdc can be modulated. With increasing concentration of the modulator, the products change from intergrown to individual crystals, the size of which can be tuned. Addition of benzoic acid also affects the size and morphology of Zr–bpdc and, additionally, makes the synthesis of Zr–bpdc highly reproducible. The control of crystal and particle size is proven by powder XRD, SEM and dynamic light scattering (DLS) measurements. Thermogravimetric analysis (TGA) and Ar sorption experiments show that the materials from modulated syntheses can be activated and that they exhibit high specific surface areas. Water proved to be essential for the formation of well‐ordered Zr–bdc–NH2. Zr–tpdc–NH2, a material with a structure analogous to that of Zr–bdc and Zr–bpdc, but with the longer, functionalized linker 2′‐amino‐1,1′:4′,1′′‐terphenyl‐4,4′′‐dicarboxylic acid, was obtained as single crystals. This allowed the first single‐crystal structural analysis of a Zr‐based metal–organic framework.
Rodlike Macromolecules through Spatial Overlapping of Thiophene Dendrons
Authors: Kimura Mutsumi , Kitao Akiko , Fukawa Tadashi , Shirai Hirofusa 
Published: May 2011

AbstractTwo novel dendritic macromonomers 7 and 8 functionalized with electroactive conjugated thiophene oligomers were synthesized by stepwise cross‐coupling reactions and the introduction of a vinyl group at the focal point. Both macromonomers were polymerized into dendronized polymers 9 and 10 by using a radical polymerization method. The photophysical and redox behaviors of dendronized polymers 9 and 10 are significantly different from those of the corresponding macromonomers. This difference may result from the spatial overlapping of thiophene dendrons through π–π interactions when the dendrons are connected to a polymer backbone. The dendronized polymers can organize into large‐area two‐dimensional sheets with a thickness of 4.8 nm. Polymer 9, which has all‐dendritic thiophene side chains, exhibited enhanced conductivity by partial doping with iodine or nitrosonium tetrafluoroborate (NOBF4). The novel amphiphilic dendronized polymer 15 was synthesized by the atom‐transfer radical polymerization of macromonomer 7 from a poly(ethylene glycol) (PEG) macroinitiator and was found to have a self‐organized structure in water.
On the Role of Intermolecular Interactions on Structural and Spin‐Crossover Properties of 2D Coordination Networks [Fe(bbtr)3]A2 (bbtr=1,4‐bis(1,2,3‐triazol‐1‐yl)butane; A=ClO4−, BF4−)
Authors: Kusz Joachim , Bronisz Robert , Zubko Maciej , Bednarek Gabriela 
Published: May 2011

AbstractA series of complexes [M(bbtr)3]A2 (M=FeII, ZnII; bbtr=1,4‐bis(1,2,3‐triazol‐1‐yl)butane; A=ClO4−, BF4−) and [FexZn1−x(bbtr)3](ClO4)2 (0<x<1) dilute systems was synthesized and characterized. Earlier studies on [Fe(bbtr)3](ClO4)2 (1⋅ClO4), which crystallizes in space group P$\bar 3$, revealed an abrupt spin transition with ${T_{1/2}^ \downarrow }$≈101 K and ${T_{1/2}^ \uparrow }$≈109 K. Variable‐temperature measurements of the lattice parameters and change in Bragg peaks profiles of 1⋅ClO4 showed a structural phase transition at 125 K leading to space group P$\bar 1$. Single‐crystal X‐ray diffraction studies allowed structures of the quenched high‐spin phase and then a low‐symmetry low‐spin phase of 1⋅ClO4 to be determined. We established that tetrafluoroborate analogue 1⋅BF4 remains in the high‐spin form in the temperature range 5–300 K. Contrary to 1⋅ClO4, structural investigations did not reveal the presence of a structural phase transition in 1⋅BF4. Analogous to 1⋅ClO4, [Zn(bbtr)3](ClO4)2 (2⋅ClO4) undergoes a structural transition at 151 K, whereas at low‐temperature [Zn(bbtr)3](BF4)2 (2⋅BF4) remains in space group P$\bar 3$. The structural phase transitions in both perchlorates are accompanied by similar reorganization of the intermolecular contacts, which leads to a shift of 2D layers. In effect, compression of the unit cell takes place, favouring the appearance of the spin transition in 1⋅ClO4 in relation to 1⋅BF4. The metal ion determines the temperature of the structural phase transition in 1⋅ClO4 and 2⋅ClO4. This property was exploited to separate the non‐magnetic structural transformation and spin transition in 1⋅ClO4. The spin and structural transitions in the [FexZn1−x(bbtr)3](ClO4)2 systems take place at different temperatures, and the temperature difference between them increases with increasing zinc(II) content. This means that structural phase transition is necessary for appearance of the spin transition, but this transformation does not trigger directly the spin transition in 1⋅ClO4.
Solid suspension in stirred tanks: UVP measurements and CFD simulations
Authors: Sardeshpande Madhavi V. , Juvekar V. A. , Ranade Vivek V. 
Published: May 2011

AbstractSuspension of solids in stirred reactor is widely used for catalytic reactions, dissolution, etc. Quality of solid suspension is an important parameter required for the reliable design, optimum performance, and scale up of the system. Quality of suspension depends on local characteristics of solid velocity and hold up profiles. The present work was focused on investigating quality of solid suspension using ultrasound velocity profiler (UVP) measurements and CFD simulations. The slip velocity measurements carried out with UVP were used to evaluate different drag correlations used in CFD simulations. Results discussed in this work would be useful for extending the applications of CFD models for simulating large stirred slurry reactors.
Cost‐effective queue schemes for reducing head‐of‐line blocking in fat‐trees
Authors: Escudero‐Sahuquillo J. , Garcia P. J. , Quiles F. J. , Flich J. , Duato J. 
Published: May 2011

SUMMARYThe fat‐tree is one of the most common topologies among the interconnection networks of the systems currently used for high‐performance parallel computing. Among other advantages, fat‐trees allow the use of simple but very efficient routing schemes. One of them is a deterministic routing algorithm that has been recently proposed, offering a similar (or better) performance than adaptive routing while reducing complexity and guaranteeing in‐order packet delivery. However, as other deterministic routing proposals, this deterministic routing algorithm cannot react when high traffic loads or hot‐spot traffic scenarios produce severe contention for the use of network resources, leading to the appearance of Head‐of‐Line (HoL) blocking, which spoils the network performance. In that sense, we describe in this paper two simple, cost‐effective strategies for dealing with the HoL‐blocking problem that may appear in fat‐trees with the aforementioned deterministic routing algorithm. From the results presented in the paper, we conclude that, in the mentioned environment, these proposals considerably reduce HoL‐blocking without significantly increasing switch complexity and the required silicon area. Copyright © 2011 John Wiley & Sons, Ltd.
Static and Dynamic Stereochemistry of Chiral Ln DOTA Analogues
Authors: Di Bari Lorenzo , Salvadori Piero 
Published: May 2011

AbstractLn DOTA derivatives (DOTA=1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid) are known to undergo relevant stereoisomeric equilibria in solution, which greatly modulate their chemical as well as their magnetic and optical properties. The subject is reviewed in terms of classical stereochemical description, with reference to conformational enthalpies. Yb is taken as the reference element because of its unique spectroscopic properties, namely, a small contact contribution to the paramagnetic shift and an intense near‐infrared electronic circular dichroism, endowed with an easily recognizable fine structure.
Chromosome remodeling and differentiation of tetraploid embryos during preimplantation development
Authors: Park Mi‐Ryung , Lee Ah‐Reum , Bui Hong‐Thuy , Park Chankyu , Park Keun‐Kyu , Cho Ssang‐Goo , Song Hyuk , Kim Jae‐Hwan , Van Thuan Nguyen , Kim Jin‐Hoi 
Published: May 2011

AbstractAlthough it is known that the tetraploid embryo contributes only to the placenta, the question of why tetraploid embryos differentiate into placenta remains unclear. To study the effect of electrofusion on the development of mouse tetraploid oocytes, mouse two‐cell embryos were fused and cultured in vitro in Chatot‐Ziomek‐Bavister medium. After electrofusion, two chromosome sets from the tetraploid blastomere were individually duplicated before nuclear fusion. At 8–10 hr after electrofusion, each chromosome set was condensing and the nuclear membrane was breaking down. Around 12–14 hr after electrofusion, the two chromosome sets had combined together and had reached the second mitotic metaphase, at this point with 8n sets of chromosomes. Interestingly, we discovered that expression of OCT4, an inner cell mass cells biomarker, is lost by the tetraploid expanded blastocysts, but that CDX2, a trophectoderm cells biomarker, is strongly expressed at this stage. This observation provides evidence clarifying why tetraploid embryos contribute only to trophectoderm. Developmental Dynamics 240:1660–1669, 2011. © 2011 Wiley‐Liss, Inc.
New Binding Modes of 1‐Acetyl‐ and 1‐Benzoyl‐5‐hydroxypyrazolines – Synthesis and Characterization of O,O′‐Pyrazoline‐ and N,O‐Pyrazoline‐Zinc Complexes
Authors: Someya Chika I. , Inoue Shigeyoshi , Irran Elisabeth , Krackl Sebastian , Enthaler Stephan 
Published: May 2011

AbstractThe 1‐acetyl‐ and 1‐benzoyl‐5‐hydroxypyrazolines 1a [3,5‐CF3, 1‐C(=O)CH3], 1b [3,5‐CH3, 1‐C(=O)CH3] and 1c [3,5‐CF3, 1‐C(=O)C6H5] have been synthesized in good yields and characterized by X‐ray crystallography. The 1‐acetyl‐ and 1‐benzoyl‐5‐hydroxypyrazoline ligands were treated with dimethylzinc in a 1:1 molar ratio to form complexes 8 with a RO–Zn–Me motif. These complexes are accessible by simple Brønsted acid–base reactions generating methane as a side product. Characterization of complexes 8a and 8c by X‐ray crystallography revealed a dimeric structure in the solid state. The two subunits generate a Zn2O2 square. The acetyl and benzoyl functionality of the ligands coordinate to the metal to span a six‐membered ring. Moreover, the coordination mode of the ligand can be easily influenced by the addition of base. Here, N,N,N′,N′‐tetramethylethylenediamine (tmeda) was applied to remove the acidic proton in the 4‐position of the ligand and to cleave the hemiaminal functional group. The tmeda‐H+ transfers the proton to the methyl group connected to the zinc and facilitates the removal of methane; the free tmeda coordinates to the zinc in a bidentate fashion. The positive charge at the zinc and the negative charge in the ligand recombine to form complex 9. Surprisingly, the characterization of complex 9c by X‐ray crystallography showed the formation of the first zinc‐based seven‐membered system with covalent bonding (N1,O6‐coordination) in the solid state, whereas for other metals O6,N2,O7‐coordination has been reported.
Retention of Symmetry Versus Desymmetrization for Bicyclo[2.2.2]octenes in the Presence of a Bridgehead Amide Group
Authors: Hren Jure , Perdih Franc , Polanc Slovenko , Kočevar Marijan 
Published: May 2011

AbstractAn efficient, microwave‐assisted and ionic‐liquid‐catalyzed esterification of bicyclo[2.2.2]oct‐7‐ene‐2,3,5,6‐tetracarboxylic acid dianhydride derivatives into the corresponding tetraesters is presented. The latter were subjected to a base‐catalyzed isomerization reaction, which proceeded with the retention of symmetry.
Incorporation of guanosine gels into sieving matrices for length‐ and sequence‐based separation of DNA in capillary electrophoresis
Authors: Dong Yingying , McGown Linda B. 
Published: May 2011

AbstractSieving gels are used in capillary gel electrophoresis to resolve DNA strands of different lengths. For complex samples, however, such as those encountered in metagenomic analysis of microbial communities or biofilms, length‐based separation may mask the true genetic diversity of the community since different organisms may contribute same‐length DNA with different sequences. There is a need, therefore, for DNA separations based on both the length and sequence. Previous work has demonstrated the ability of guanosine gels (G‐gels) to separate four single‐stranded DNA 76‐mers that differ by only a few A/G base substitutions. The goal of the present work is to determine whether G‐gels could be combined with commercial sieving gels in order to simultaneously separate DNA based on both length and sequence. The results are given for the four 76‐mers and for a standard dsDNA ladder. Commercial sieving gels were used alone and in combination with G‐gels. For the 76‐mers, the combined medium was less efficient than the G‐gel alone but was able to achieve partial resolution. The combined medium was at least as effective as the sieving gel alone at resolving the denatured DNA ladder and showed indications of sequence‐based resolution as well, as supported by MALDI‐MS. The results show that the combined sieving gel/G‐gel medium retains the selectivity of the individual media, providing a promising approach to simultaneous length‐ and sequence‐based DNA separation for metagenomic analysis of complex systems.
Ion‐permeable membrane for on‐chip preconcentration and separation of cancer marker proteins
Authors: Nge Pamela N. , Yang Weichun , Pagaduan Jayson V. , Woolley Adam T. 
Published: May 2011

AbstractCancer marker proteins have been electrophoretically concentrated and then separated in a microfluidic device. On‐chip preconcentration was achieved using an ion‐permeable membrane, consisting of acrylamide, N,N′‐methylene‐bisacrylamide and 2‐(acrylamido)‐2‐methylpropanesulfonate. This negatively charged membrane was photopolymerized in the microdevice near the injection intersection. Anionic proteins were excluded from the porous membrane based on both size and charge, which concentrated target components in the injection intersection prior to separation by microchip capillary electrophoresis (μ‐CE). Bovine serum albumin was used in the initial characterization of the system and showed a 40‐fold enrichment in the μ‐CE peak with 4 min of preconcentration. Adjustment of buffer pH enabled baseline resolution of two cancer biomarkers, α‐fetoprotein (AFP) and heat shock protein 90 (HSP90), while fine control over preconcentration time limited peak broadening. Our optimized preconcentration and μ‐CE approach was applied to AFP and HSP90, where enrichment factors of >10‐fold were achieved with just 1 min of preconcentration. Overall, the process was simple and rapid, providing a useful tool for improving detection in microscale systems.