bluuebunny/crossref_metadata_2025_split huggingface dataset:
Signalübertragung und leitende Kunststoffe
Authors: Maelicke Alfred 
Published: May 2010

AbstractMit dem Nobelpreis für Chemie wurden Arbeiten ausgezeichnet, die der Polymerchemie und der modernen Materialforschung wesentliche Impulse gegeben haben. Der Nobelpreis für Medizin oder Physiologie ist in diesem Jahr an drei Neurowissenschaftler gegangen, die grundlegende Arbeiten zur Signalübertragung im Gehirn geleistet haben.
TROSY und Co: NMR‐Methoden für die Wirkstoffentwicklung
Authors: Maurer Till 
Published: May 2010

AbstractNoch dominiert die Röntgenkristallographie die Strukturbestimmung von Proteinen. Aber die hochauflösende NMR‐Spektroskopie holt auf. Die Größe der Proteine spielt für NMR‐Untersuchungen nun (fast) keine Rolle mehr: Molekulargewichte von mehr als 200 kDa sind mittlerweile im Bereich des Möglichen ‐ dank neuer Methoden, aber auch durch die technische Weiterentwicklung der NMR‐Spektrometer.
Magie, die im Kind den Chemiker weckt
Authors: Wagner Tobias , Schmidt Thomas 
Published: May 2010

AbstractExperimentierkästen haben sicherlich einen nicht zu unterschätzenden Anteil am besseren Verständnis und ausgeprägteren Interesse an der Chemie in der Schule; vielleicht sind sie sogar Schuld am späteren Chemiestudium des ein oder anderen, indem sie eine Faszination am Experiment entfacht haben, die bis heute nicht mehr erloschen ist. Doch wie steht es heute um die Chemiebaukästen?
1282 chemische Bachelor‐und Master–Studiengänge in Großbritannien
Authors: Kuhnert Nikolai 
Published: May 2010

AbstractDer Trend an den britischen Hochschulen geht dahin, den Master zum meistgewählten Studienabschluss zu machen und den Bachelor der fehlenden internationalen Vergleichbarkeit wegen abzuschaffen. Um die Studenten zu halten, bieten die etwa 70 Hochschulen im Fach Chemie 1282 verschiedene Studiengänge und Abschlüsse an.
Computer und Indigo ‐ Alles öko?
Authors: Gärtner Edgar 
Published: May 2010

AbstractIndikatoren, mit denen sich die Umweltverträglichkeit chemischer Produkte und Methoden einschätzen lässt, unterstützen auch die Lernprozesse in den Unternehmen. Wie tragen positive Parameter für Ökoeffizienz und soziale Verträglichkeit zum Wert eines Unternehmens bei?
Teaching and Research for a Closer‐Knit Europe
Authors: Karger Gerhard 
Published: May 2010

AbstractRudolf Zahradnik, President of the Academy of Sciences of the Czech Republic – and an enthusiast when it comes to Europe – has markedly influenced the reform process in his own country. His point of view has never been limited exclusively to science but has always been part of a European vision. In the following interview, Professor Zahradnik ‐ an honorary member of the GDCh since 18th September 2000 – expresses his views on European expansion and its influence on teaching and research in the Czech Republic specifically and in Europe as a whole.
Regulatoren der Apoptose: Ziele für die Arzneimittelentwicklung
Authors: Maelicke Alfred 
Published: May 2010

AbstractDer programmierte Zelltod (Apoptose) ist ein für die Entwicklung und Aufrechterhaltung eines multizellulären Organismus lebenswichtiger Mechanismus. Ausgeschaltet oder überaktiviert kann Apoptose aber auch zu schweren Erkrankungen führen. Mit dem neuen Protein Diablo/Smac ist kürzlich ein weiterer Regulator der Apoptose entdeckt worden.
Endnote 4 ‐ Jäger und Sammler
Authors: Velten Christian , Informationsdienste Scitari 
Published: May 2010

AbstractKlassiker kann man nicht besser machen, behaupten viele. Die Entwickler der Literaturverwaltungssoftware Endnote beweisen das Gegenteil. Durch Implementierung von Onlinefunktionen ist Endnote zu einem Allroundtalent für Literatursuche und Literaturverwaltung geworden.
Gibt es das überhaupt: „Spezialchemikalien”︁?
Authors: Willers Yves , Jung Udo 
Published: May 2010

AbstractDie Unterscheidung zwischen Basis‐ und Spezialchemikalien nimmt an Bedeutung zu, da immer mehr Chemiefirmen gegenüber den Investoren eine „Spezialchemie‐Story”︁ beanspruchen. Die Frage ist jedoch, ob ein „Spezialchemie‐Produktportfolio”︁ im Vergleich zum Chemie‐Branchenindex eine bessere Bewertung verdient.
Life–Cycle‐Management plus Technologieplattform
Authors: Hauthal Hermann G. 
Published: May 2010

AbstractMit Life ‐Cycle–Management, höherer Effizienz und einer der weltweit besten, Technologieplattformen, umfangreiche Genomics– und Bioinformatik–Kooperationen inclusive, will Bayer Pharma vorerst vor allem aus eigener Kraft weiter wachsen. In diesem Jahr werden erstmalig zehn Entwicklungskandidaten für neue Medikamente erwartet.
Mit S‐S‐reduzierendem Reagenz und CE‐LIF
Authors: Caussé E. , Malatray P. , Bayle Toulouse C. , Couderc F 
Published: May 2010

AbstractDie laserinduzierte Fluoreszenz eignet sich als ein sehr schnelles Verfahren für die Detektion von Thiolen in Plasma. Es gelingt die Trennung von Homocystein und verschiedenen Thiolen, die im Metabolismus von Glutathion beteiligt sind.
Promotion ‐ und was dann? Arbeitgeber Chemische Industrie
Authors: Siekerkötter Reiner 
Published: May 2010

AbstractWie sind die Chancen für promovierte Chemiker, in der chemischen Industrie eingestellt zu werden? Welche Aufgaben übernehmen Chemiker in den Unternehmen? Gibt es spezielle Bewerbungsstrategien? Was regeln Arbeitsverträge? Welche Standards sind zumindest in der Großchemie üblich?
DNA als Konstruktionsmaterial für die Nanotechnologie
Authors: Niemeyer C. 
Published: May 2010

AbstractBeflügelt durch eindrucksvolle Vorbilder aus der belebten Natur erwächst ein zunehmendes Interesse, Biomoleküle und biomimetische Aufbauprinzipien bei der Herstellung nanodimensionierter Materialien einzusetzen. Das Erbmolekül DNA ist ein besonders geeigneter Werkstoff für die Nanowissenschaften.
Katalyse heute ‐ gelingt der Brückenschlag?
Authors: Grünert Wolfgang 
Published: May 2010

AbstractDas Bemühen urn Brückenschläge zwischen Grundlagenforschung und Anwendung prägt das Forschungsgeschehen in der heterogenen Katalyse. Das Vordringen des kombinatorischen Ansatzes in die heterogene Katalyse hat eher Gräben aufgerissen ‐ doch die Diskussion auf dem 12. Internationalen Katalysekongress deutet auch hier mögliche Brückenschläge an.
Nebel, Spot, Fanfare‐Wie Schüler noch Chemie lernen können
Authors: Kerk Andrea , Dücker‐Benfer Carlos , Schneppensiepe Thorsten , Müller Bernd , Calle Michael , van Eldik Rudi , Felser Claudia , Renz Franz , Tremel Wolflgang , Zimehl Ralf , Drieß Matthias 
Published: May 2010

AbstractAn immer mehr Chemiefachbereichen in deutschen Universitäten finden sich Professoren und Studenten, die mit viel Zeit, Fleiß und persönlichem Engagement Versuchstage, Schnupperwochenenden oder aufwendige Experimentalvorlesungen für die Öffentlichkeit und vor allem für Schüler auf die Beine stellen. Und alle verfolgen damit das gleiche Ziel: Chemie erlebbar und spannend zu machen und ihre Begeisterung für Chemie auf das Publikum zu übertragen.
„Noch haben wir keine Probleme…”︁
Authors: Schaper Iris , Matzen Matthias , Matzen Medienburo 
Published: May 2010

AbstractSchon jetzt werben Professoren in Stellenanzeigen mit immer blumigeren Worten urn wissenschaftliche Nachwuchskräfte. Doch wie sehen das die Chemie‐Unternehmen? Entwickeln sie neue Werbestrategien für Hochschulabsolventen oder zeigen sie sich vom angekündigten Chemikermangel unbeeindruckt?
Biozid‐Produkte werden sicherer
Authors: Gärtner Sabine 
Published: May 2010

AbstractDie EU‐Kommission hat eine Verordnung über die erste Stufe des Programms zur Überprüfung alter Wirkstoffe in Bioziden erlassen. Diese Verordnung soll dahin führen, dass in spätestens zehn Jahren nur noch überprüfte Wirkstoffe in Bioziden in Verkehr gebracht werden dürfen.
Franz Hein, Arthur Schleede, Hans Kautsky und die Anorganische Chemie in Leipzig
Authors: Beyer Lothar , Hoyer Eberhard 
Published: May 2010

AbstractHätten Sie's gewußt? Arenkomplexe, Alkalimetall‐Graphit‐Einlagerungsstrukturen und Singulett‐Sauerstoff ‐ all diese hochaktuellen Forschungsgebiete haben ihren Ursprung in der anorganischen Abteilung am Chemischen Laboratorium der Universität Leipzig.
Chemische Visualisierung im WorldWideWeb
Authors: Oellien Frank , Engel Thomas , Hemmer Markus C. 
Published: May 2010

AbstractWer chemische Strukturen in Webbrowsern darstellen möchte, muss diese für die speziellen Datenformate mit Plug‐ins, Java‐Applets oder Active‐X‐Controls aufrüsten. Immer mehr Plug‐ins sind eigenständige Anwendungen, die innerhalb eines Browserfensters ablaufen können.
DPMA: Mehr Prüfer gegen den Patentstau
Authors: Horn Anselm , Hauthal Hermann G. 
Published: May 2010

AbstractIm 50. Jahr seines Bestehens weist das Deutsche Patent‐ und Markenamt erneut einen zweistelligen Zuwachs bei deutschen Patentanmeldungen aus. Die Chemie spielt auf den vorderen Plätzen etwas zurückhaltender mit.
A method for selecting and monitoring medication sales for surveillance of gastroenteritis
Authors: Pelat Camille , Boëlle Pierre‐Yves , Turbelin Clément , Lambert Bruno , Valleron Alain‐Jacques 
Published: May 2010

AbstractPurposeMonitoring appropriate categories of medication sales can provide early warning of certain disease outbreaks. This paper presents a methodology for choosing and monitoring medication sales relevant for the surveillance of gastroenteritis and assesses the operational characteristics of the selected medications for early warning.MethodsAcute diarrhoea incidences in mainland France were obtained from the Sentinelles network surveillance system for the period 2000–2009. Medication sales grouped by therapeutic classes were obtained on the same period. Hierarchical clustering was used to select therapeutic classes correlating with disease incidence over the period. Alert thresholds were defined for the selected therapeutic classes. Single and multiple voter algorithms were investigated for outbreak detection based on sales crossing the thresholds. Sensitivity and specificity were calculated respective to known outbreaks periods.ResultsFour therapeutic classes were found to cluster with acute diarrhoea incidence. The therapeutic class other antiemetic and antinauseants had the best sensitivity (100%) and timeliness (1.625 weeks before official alerts), for a false alarm rate of 5%. Multiple voter algorithm was the most efficient with the rule: ‘Emit an outbreak alert when at least three therapeutic classes are over their threshold’ (sensitivity 100%, specificity 95%, timeliness 1.750 weeks before official alerts).ConclusionsThe presented method allowed selection of relevant therapeutic classes for surveillance of a specific condition. Multiple voter algorithm based on several therapeutic classes performed slightly better than the best therapeutic class alone, while improving robustness against abrupt changes occurring in a single therapeutic class. Copyright © 2010 John Wiley & Sons, Ltd.
On‐line opto‐viscoelastic analysis of polypropylene fibres using multiple‐beam Fizeau fringes in transmission and a modified creep device
Authors: Hamza Ahmad A , Sokkar Taha ZN , El‐Farahaty Kermal A , Raslan Mohammed I 
Published: May 2010

AbstractA creep device attached to an automated multiple‐beam Fizeau system in transmission was modified with a designed digital ruler. This device allows on‐line measurements of fibre length during creep experiments in terms of an analogue voltage value. The influence of sustained stress values on creep deformation and optical properties (n||, n⟂ and Δn) for polypropylene (PP) fibres was studied interferometrically. The opto‐viscoelastic properties of PP fibres were determined for three different values of constant applied stress of 11.536, 18.717 and 25.905 MPa, at room temperature. Also, the variations of the cross‐sectional area and Poisson's ratio were studied during creep extensions. The compliance curves were obtained as a function of both time and applied stresses. Empirical formulae are suggested to describe the creep compliance curves for PP fibres, and the constants of these formulae were determined and described at each applied stress. A Kelvin chain was used to model the mechanical behaviour of the PP fibres under study. The effect of strain on the mean refractive indices, orientation function density and crystallinity was investigated as a result of the recorded data. Microinterferograms are given for illustration. The modified creep device with the designed digital ruler enables one to obtain instantaneous automatic accurate recording of fibre length values during creep experiments. Calculation of refractive indices, orientation function and crystallinity shows a difference in material behaviour at small stresses from that at higher stresses which may be attributed to different strain rates caused by different stresses. Copyright © 2010 Society of Chemical Industry
Autonomous damage initiated healing in a thermo‐responsive ionomer
Authors: Varley Russell John , van der Zwaag Sybrand 
Published: May 2010

AbstractThe partially neutralised poly[ethylene‐co‐(methacrylic acid)] copolymer Surlyn 8940® (DuPont) ionomer exhibits damage‐initiated healing during high‐energy impact. This is attributed to the hierarchical structure of ionomers, arising from the presence of ionic aggregates and hydrogen bonding. This work investigates the mechanism of this process using novel techniques developed here. The ionomer's response to penetration has been found to consist of three consecutive events: an initial elastic response, an anelastic response and pseudo‐brittle failure. In addition, the ultimate level of healing has been shown to be dependent upon the elastic response during impact as well as post‐failure viscous flow. Increasing the local temperature at impact consistently increases elastic healing, although further improvements in healing are minor once the local temperature increases beyond the melting point. Below the order‐to‐disorder transition, microscopic investigations reveal severe plastic deformation while the lack of shape memory reduces the comparative level of elastic healing. Above this temperature, healing is facilitated by elastomeric behaviour at the impact site, while above the melting point a combination of elastomeric and viscous flow dominates. This work provides for the first time evidence of the consecutive healing events occurring during high‐impact penetration for ionomers. The hierarchical structure of ionomers and its impact upon the microstructure have been shown to be critical to the process. Comparison of the mechanical response during impact with that of non‐ionic polymers further highlights this. In addition, slow relaxational processes occurring post‐impact are found to facilitate further recovery in mechanical properties. Copyright © 2010 Society of Chemical Industry
Bioconversion of dieldrin by wood‐rotting fungi and metabolite detection
Authors: Kamei Ichiro , Takagi Kazuhiro , Kondo Ryuichiro 
Published: May 2010

AbstractBACKGROUND: Dieldrin is one of the most persistent organochlorine pesticides, listed as one of the 12 persistent organic pollutants in the Stockholm Convention. Although microbial degradation is an effective way to remediate environmental pollutants, reports on aerobic microbial degradation of dieldrin are limited. Wood‐rotting fungi can degrade a wide spectrum of recalcitrant organopollutants, and an attempt has been made to select wood‐rotting fungi that can degrade dieldrin, and to identify the metabolite.RESULTS: Thirty‐four isolates of wood‐rotting fungi were investigated for their ability to degrade dieldrin. Strain YK543 degraded 39.1 ± 8.8% of dieldrin during 30 days of incubation. Phylogenetic analysis demonstrated that strain YK543 was closely related to the fungus Phlebia brevispora Nakasone TMIC33929, which has been reported as a fungus that can degrade chlorinated dioxins and polychlorinated biphenyls. 9‐Hydroxydieldrin was detected as a metabolite in the cultures of strain YK543.CONCLUSION: It is important to select the microorganisms that degrade organic pollutants, and to identify the metabolic pathway for the development of bioremediation methods. Strain YK543 was selected as a fungus capable of degrading dieldrin. The metabolic pathway includes 9‐hydroxylation reported in rat's metabolism catalysed by liver microsomal monooxygenase. This is the first report of transformation of dieldrin to 9‐hydroxydieldrin by a microorganism. Copyright © 2010 Society of Chemical Industry
AlN substrates and epitaxy results
Authors: Helava Heikki , Chemekova Tat'jana , Avdeev Oleg , Mokhov Eugeny , Nagalyuk Sergey , Makarov Yuri , Ramm Mark 
Published: May 2010

AbstractAluminum nitride (AlN) is a true bulk‐grown native substrate for III‐nitrides. The crystals are grown by seeded physical vapor transport (PVT) using AlN seeds. AlN has high thermal conductivity (comparable to, and perhaps higher than SiC), high bulk resistivity (>1x1011 Ohm cm), high bulk‐breakdown field (7‐8 MV/cm), the highest surface acoustic wave (SAW) velocity and since it has the smallest lattice constant of the III‐nitrides all AlInGaN compositions grown on AlN are in compression, thus making it easier to grow crack‐free epitaxy. Additionally, AlN is transparent down to nearly 200 nm, making it attractive for deep UV LED structures. AlN has excellent cleavage planes making it suitable for edge‐emitting lasers and low cost manufacturing. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural differences in Mg‐doped InN – indication of polytypism
Authors: Liliental‐Weber Z. , Hawkridge M. E. , Wang X. , Yoshikawa A. 
Published: May 2010

AbstractTransmission Electron Microscopy shows that the InN samples doped with either increasing or constant Mg concentration follow a cation or anion substrate polarity. In‐polar samples change growth polarity when the Mg concentration is >1019cm‐3. N‐polar samples have much higher density of planar defects than In‐polar samples and their presence leads to a decrease in dislocation density. In the N‐polar samples equally spaced planar defects are observed for Mg concentration >1019cm‐3. Three different polytypes (2H, 3C and 4H) were observed in this type of samples. A band of planar defects with thick layers of a cubic material (3C) is observed for Mg concentration >1020cm‐3. At this Mg concentration only n‐type conductivity was reported earlier. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A precise ray tracing simulation model for GaN based light emitting diodes
Authors: Yang Zhiyuan , Yu Tongjun , Mu Sen , Chen Zhizhong , Zhang Guoyi 
Published: May 2010

AbstractA simulation model for light extraction efficiency (LEE) was proposed, considering the real structure of GaN_based light emitting diodes and absorption of GaN, electrodes and encapsulation materials, as well as the difference between TE and TM modes, the effects of active layer reabsoption and photo recycling. The slope angle and the depth of the pattern were optimized for patterned sapphire substrates (PSSs). Results show fill factor affects the LEE improvement most and air holes buried in the interface between n‐GaN and PSS diminish LEE improvement of the pattern. Then a best improvement of 26% is obtained with the optimized pattern. Especially it is noticeable that the simulated result of LEE (39.2%) and the derived internal quantum efficiency (43.9%) agree well with the experimental results (38%, 45.1% respectively). (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Internal quantum efficiency of GaN/AlGaN‐based multi quantum wells on different dislocation densities underlying layers
Authors: Takeda Kenichiro , Mori Fumiaki , Ogiso Yuji , Ichikawa Tomoaki , Nonaka Kentaro , Iwaya Motoaki , Kamiyama Satoshi , Amano Hiroshi , Akasaki Isamu 
Published: May 2010

AbstractInternal quantum efficiency (IQE) of GaN/AlGaN multi quantum wells on the low dislocation density Al0.25Ga0.75N grown by epitaxial lateral overgrowth (ELO) and facet controlled epitaxial lateral overgrowth were investigated by excitation intensity dependent photoluminescence measurement. The threading dislocation density decreased from 4x109cm‐2 to 2x108cm‐2 by using ELO method, then the IQE was much improved from 5% to 40% when the carrier density was 1x1018cm‐3. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of trapping effects in AlGaN/GaN HEMTs based on near zero bias output conductance
Authors: Kim Hyeongnam , Lu Wu 
Published: May 2010

AbstractA simple model is developed for characterization of current collapse caused by electron trapping in AlGaN/GaN HEMTs. Threshold voltages are extracted from near‐zero drain bias output conductance characteristics with respect to gate bias based on 0.2 μs pulsed I –V characteristics at different quiescent bias points. Other device parameters such as effective gate length and electron mobility are also estimated by fitting to a model equation. The results show that a higher negative electric field between gate and drain contacts cause a higher threshold voltage shift in the positive direction and a longer effective gate length, resulting in a larger current dispersion due to trapping of more electrons. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrical characterization of n ‐GaN epilayers using transparent polyaniline Schottky contacts
Authors: Nakano Yoshitaka , Matsuki Nobuyuki , Irokawa Yoshihiro , Sumiya Masatomo 
Published: May 2010

AbstractWe have successfully investigated deep levels of n ‐GaN epilayers with high carrier concentrations by using transparent polyaniline Schottky conctacts. High quality Schottky barrier diodes fabricated showed a capacitance dispersion phenomenon at ∼10 kHz, which is characteristic of polyaniline. Deep‐level optical spectroscopy measurements above this cutoff frequency newly revealed a specific deep levels located at ∼1.70 eV below the conduction band, being different from the deep levels commonly observed in GaN. This deep level showed a significant increase in steady‐state photocapacitance with a decrease in probing depth range. Therefore, the 1.70 eV level probably stems from the near‐surface region of the n ‐GaN rather than the bulk region. This is the abstract. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Carrier injection in InAlGaN single and multi‐quantum‐well ultraviolet light emitting diodes
Authors: Kolbe Tim , Sembdner Toni , Knauer Arne , Kueller Viola , Rodriguez Hernan , Einfeldt Sven , Vogt Patrick , Weyers Markus , Kneissl Michael 
Published: May 2010

Abstract316 nm (In)AlGaN light emitting diodes (LEDs) with one, three, five and seven quantum wells (QWs) have been investigated. The carrier injection in the devices is simulated and compared with electroluminescence measurements. The emission power of all LEDs is nearly the same at low currents. This effect is attributed to the inhomogeneous carrier distribution in the QWs of the multi‐quantum‐well (MQW) structures. Only the first two QWs closest to the p‐side of the diode contribute significantly to the optical emission (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)