bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of the Crossover From Simple Liquid‐Like to a Polymer‐Like Behavior of Polyisoprene by Means of MD Simulations
Authors: Sacristan Javier 
Published: July 2010

AbstractThe crossover from small‐molecule to polymer behavior in realistic models of PI at temperatures well above the glass transition is investigated by means of MD simulations. The molar masses range from the monomer to $\overline {M} _{{\rm w}} $ = 6 800 g · mol−1 which is far from the critical value for entanglement in PI. It is shown that at this temperature the non‐Gaussian parameter almost vanishes in the Q‐range studied. This implies Gaussian behavior in almost all the Q‐range. From the mean square displacement and the incoherent scattering function behavior a smooth transition from the microscopic regime to the Rouse dynamics is observed. The Rouse behavior is achieved at chain molecular weights of about 1 000 g · mol−1, which corresponds to 14 monomer units.magnified image
Delayed contrast‐enhanced MRI of cartilage: Comparison of nonionic and ionic contrast agents
Authors: Li Wei , Scheidegger Rachel , Wu Ying , Edelman Robert R. , Farley Michelle , Krishnan Nitya , Burstein Deborah , Prasad Pottumarthi V. 
Published: July 2010

AbstractThe objective of this study was to evaluate if cartilage fixed charge density is the only factor determining the distribution of the measured delayed gadolinium‐enhanced magnetic resonance imaging of cartilage index, T1(Gd‐DTPA2−), across cartilage in the clinical delayed gadolinium‐enhanced magnetic resonance imaging of cartilage protocol. Nineteen subjects with osteoarthritis and 14 controls were included. Cartilage T1(Gd) was measured following administration of 0.2 mmol kg−1 of nonionic (Gd‐DTPA‐BMA) and, at a different date, anionic (Gd‐DTPA2−). T1(Gd‐DTPA‐BMA) was plotted against T1(Gd‐DTPA2−); a slope of 0 would indicate domination by charge effects; a nonzero slope would suggest that other factors influence T1(Gd‐DTPA‐BMA), and hence potentially T1(Gd‐DTPA2−). The low slope of the curve found in osteoarthritis subjects (0.31) indicates that Gd‐DTPA‐BMA penetrated most osteoarthritis cartilage to the same extent, and T1(Gd‐DTPA‐BMA) did not differentiate cartilages, which were differentiated by T1(Gd‐DTPA2−). The higher slopes in control subjects (0.88) are possibly due to inhibited transport of contrast agent into healthier cartilage, potentially exaggerated by the fast body clearance of the nonionic contrast agent. Overall, the use of anionic Gd‐DTPA2− for delayed gadolinium‐enhanced magnetic resonance imaging of cartilage is indicated for better discrimination of the health status of cartilage. Future studies could be designed to use contrast‐enhanced dynamics to understand the transport properties of tissues in the joint and to evaluate the concentration of tissue constituents. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Transmit/receive radiofrequency coil with individually shielded elements
Authors: Gilbert Kyle M. , Curtis Andrew T. , Gati Joseph S. , Martyn Klassen L. , Villemaire Lauren E. , Menon Ravi S. 
Published: July 2010

AbstractA novel method for decoupling coil elements of transmit/receive (transceive) arrays is reported. Each element of a coil array is shielded both concentrically and radially to reduce the magnetic flux linkage between neighboring coils; this substantially reduces the mutual inductance between coil elements and allows them to behave independently. A six‐channel transceive coil was developed using this decoupling scheme and compared with two conventional decoupling schemes: the partial overlapping of adjacent elements and capacitive decoupling. The radiofrequency coils were designed to image the human head and were tested on a 7‐T Varian scanner. The decoupling, transmit uniformity, transmit efficiency, signal‐to‐noise ratio, and geometry factors were compared between coils. The individually shielded coil achieved higher minimum isolation between elements (2.7–4.0 dB) and lower geometry factors (2–14%) than the overlapped and capacitively decoupled coils, while showing a reduction in transmit efficiency (2.8–5.9 dB) and signal‐to‐noise ratio (up to 34%). No difference was found in the power absorbed by the sample during a 90° radiofrequency pulse. The inset distance of coil elements within their shields was then reduced, resulting in significant improvement of the transmit efficiency (1.3 dB) and signal‐to‐noise ratio (28%). The greatest asset of this decoupling method lies in its versatility: transceive coils can be created with elements of arbitrary shape, size, location, and resonant frequency to produce three‐dimensional conformal arrays. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Ein Knochenjob für die Biomimetik
Authors: Fratzl Peter 
Published: July 2010

AbstractDie Struktur‐Funktions‐Analyse eines Knochens zeigt, wie sein hierarchischer Aufbau zu Biegefestigkeit und Rissbeständigkeit führt. Bioinspirierte Forschung erfordert moderne physikalisch‐chemische Methoden und Chemiker, welche die Erkenntnisse aus der Natur in Materialien umsetzen.
Die Struktur‐ und Bioassaydatenbank PubChem
Authors: Ihlenfeldt Wolf‐D. 
Published: July 2010

AbstractBioassays und zugehörige Strukturen sind in der freien Datenbank PubChem zu finden. Forscher liefern ihre Ergebnisse in dieses öffentliche Projekt und greifen auf die Resultate anderer zu.
Totalsynthese des Telomerase‐Inhibitors UCS1025A
Authors: Rüping. Magnus 
Published: July 2010

AbstractOb “sanfte” Enolisierung‐Cyclisierung, Oxa‐Michael‐Lactonisierung/Digerier‐Verfahren oder organokatalytische Diels‐Alder‐Reaktion – der einfache Zugang zu größeren Mengen des Telomerase‐Inhibitors ( )‐UCS1025A und Analoga ist gefunden und der Weg zu Struktur‐Wirkungs‐Studien frei.
Isotopenanalyse – ein neues Werkzeug in der Umweltanalytik
Authors: Schmidt Torsten C. , Jochmann Maik A. , Blessing Michaela 
Published: July 2010

AbstractDie substanzspezifische Isotopenanalytik ist vor allem aus zwei Bereichen bekannt: aus der Authentizitätskontrolle in der Lebensmittelüberwachung und aus der Dopinganalytik im Sport. Weniger bekannt sind die Anwendungen aus der Umweltanalytik – etwa bei der Altlastensanierung an Industriestandorten.
Familienbewusste Chemieindustrie
Authors: Rabe Christiane 
Published: July 2010

AbstractDie Vereinbarkeit von Beruf und Familie zu fördern, ist inzwischen auch für Unternehmen der Chemiebranche erstrebenswert geworden. Familienfreundliche Strukturen machen einen Arbeitgeber attraktiv für potenzielle neue Mitarbeiter.
Anorganische Festkörperchemie im Konzert der Materialforschung
Authors: Jansen Martin 
Published: July 2010

AbstractViele Chemiker träumen davon, neue Materialien mit spezifikationsgerechten Eigenschaften herzustellen – Begriffe wie “Maßschneidern” oder “Design” haben Hochkonjunktur. In Wirklichkeit ist die Synthese von neuen Festkörpern aber mit vielen Unwägbarkeiten behaftet. Gelänge es, den Bestand existenzfähiger Stoffe zu katalogisieren, ließe sich im Dialog “Synthese‐Anwendung” die Entdeckung neuer Materialien stark befördern.
Die Last des Kohlenstoffs
Authors: Guggolz Ernst 
Published: July 2010

AbstractDa sitzen die Regierungsvertreter in Nairobi und beschließen “nichts, was die Erde vor immer mehr Kohlenstoff bewahren würde”. Nicht nur die Erde, auch die Zeitschriftenredaktionen erwiesen sich so im vergangenen Jahr als Schnelle Brüter. Ein Trendbericht.
Iminooxadiazindione: vom Nebenprodukt zur Leitstruktur
Authors: Richter Frank 
Published: July 2010

AbstractDie vor etwa zehn Jahren begonnene Erforschung des Reaktionsverhaltens von Hexahydrotoluylendiisocyanat hatte ein unerwartetes Ergebnis: Die polycyclischen Iminooxadiazindione waren entdeckt. Dabei gewonnene Erkenntnisse führten zu einer neuen Klasse von Härtern für die Lackindustrie.
Nanostrukturen erstrahlen in neuem Licht
Authors: Hartschuh Achim 
Published: July 2010

AbstractEine laserbeleuchtete Metallspitze verstärkt die optischen Signale einzelner Nanostrukturen. So belichtet, lassen sich Raman‐ und Photolumineszenzbilder mit einer Ortsauflösung von 10 nm simultan aufnehmen.
Informationen über die Wasserqualität
Authors: Vogel Eva , Aichert Albert 
Published: July 2010

AbstractDer chemische Sauerstoffbedarf von Oberflächenwasser, Trinkwasser und Abwasser aus Industrie oder Privathaushalten gibt an, wie viel oxidierbares organisches Material sie enthalten. Dieser Wert wird über Rücktitration bestimmt, die auch vollautomatisch möglich ist.
Habilitationen, weibliche Professoren und Juniorprofessoren
Authors: Schmitz Karin 
Published: July 2010

AbstractZum zweiten Mal nach 2004 wurden Ende vergangenen Jahres die Dekanate der Chemiefakultäten nach Anzahl und Fachrichtung der Habilitanden und Juniorprofessuren, der abgeschlossenen Habilitationen und der Zahl der weiblichen C3‐ und C4‐Professoren gefragt. Die GDCh dankt allen Ansprechpartnern an den Hochschulen, die die Daten ihrer Fakultäten zur Verfügung gestellt haben.
Der erweiterte Nutzen von Chemikalienschutzanzügen
Authors: Bulmahn Maren 
Published: July 2010

AbstractSchutzanzüge bewahren ihr Inneres vor Schaden. Bestimmte Farben und Materialien unterstützen zusätzlich ihre Träger in ihrem Wohlbefinden: Türkis macht Mut, Grün vermittelt Ruhe, Braun vertreibt Stress und Rot erhöht das Selbstbewusstsein.
Der Europäische Forschungsrat: eine Chance ohnegleichen
Authors: Freund Hans‐Joachim 
Published: July 2010

AbstractDer Europäische Forschungsrat fördert beim 7. Forschungsrahmenprogramm Grundlagenforschung nur aufgrund ihrer wissenschaftlichen Qualität. Themen aus der Chemie sind mehrfach vertreten und Chemiker sollten diese Chance nutzen.
Beim Frauenanteil Schlusslicht in Europa
Authors: Bulmahn Maren 
Published: July 2010

AbstractDie Gleichberechtigung ist in vielen Programmen und Satzungen festgeschrieben. Jetzt kommt es darauf an, in Forschung und Wissenschaft die richtigen Steuerungsinstrumente zu nutzen und geschlechterspezifische Aspekte als Chance und Auftrag zu erkennen.
Correlation of urinary excretion of sodium with severity of sleep‐disordered breathing in children: A preliminary study
Authors: Kaditis Athanasios G. , Alexopoulos Emmanouel I. , Evangelopoulos Konstantinos , Kostadima Eleni , Varlami Vasiliki , Boultadakis Evangelos , Liakos Nikolaos , Zakynthinos Epameinondas , Zintzaras Elias , Gourgoulianis Konstantinos 
Published: July 2010

AbstractBackgroundNocturnal urinary sodium excretion is related to blood pressure (BP) levels. Elevated BP and increased nocturnal natriuresis have been demonstrated in adults with sleep apnea. Although evidence indicates increased BP in children with obstructive sleep‐disordered breathing (SDB), it is unknown whether these children have also enhanced urinary sodium excretion.ObjectiveTo evaluate the effects of SDB and morning BP on urinary sodium excretion.MethodsConsecutive children with snoring (n = 95) underwent polysomnography and morning BP measurement. Fractional excretion of sodium (FENa) was the primary outcome measure and was calculated using sodium and creatinine concentrations in early morning serum and urine specimens.ResultsSubjects with moderate‐to‐severe SDB had similar log‐transformed FENa to that of children with mild SDB and higher than children with primary snoring: −0.13 ± 0.53 versus −0.28 ± 0.41 versus −0.61 ± 0.65 (P = 0.657 and P = 0.003). Obstructive apnea–hypopnea index was significantly related to FENa after adjustment for age, gender and body mass index z‐score (P = 0.002). Children with moderate‐to‐severe SDB had similar systolic BP z‐scores to those of subjects with mild SDB and higher than participants with primary snoring: 0.7 ± 1.2 versus 0.1 ± 1.0 versus −0.02 ± 1.0 (P = 0.074 and P = 0.046). In addition, participants with diastolic BP z‐scores in the upper quartile of measured values had higher FENa than subjects with z‐scores in the lower quartiles: −0.08 ± 0.39 versus −0.41 ± 0.57 (P = 0.007).ConclusionsMorning natriuresis is related to severity of SDB in children and this association may be mediated in part by elevated BP. Pediatr Pulmonol. 2010; 45:999–1004. © 2010 Wiley‐Liss, Inc.
Clinical characteristics of Korean pediatric patients critically ill with influenza A (H1N1) virus
Authors: Shin Soo Youn , Kim Joon Hyung , Kim Hyun Su , Kang Young A , Lee Ha Gyung , Kim Jin Seok , Lee Jong‐Koo , Kim Woo Kyung 
Published: July 2010

AbstractBackgroundNovel influenza A (H1N1) virus infection has persisted mainly through person‐to‐person transmission in schools. However, data on critically ill patients infected with H1N1 are currently limited. This study was conducted to investigate the epidemiological characteristics, clinical features, treatment modalities, and clinical outcomes of pediatric patients critically ill with H1N1 infection.MethodsSubjects included 30 critically ill pediatric patients reported to the Korea Centers for Disease Control and Prevention (KCDC) between June and November 2009. Data were obtained by medical record review and interviews with primary treating physician.ResultsOf the 30 patients, 14 died and 16 were discharged from the hospital with complete recovery. The median patient age was 7 years (range, 2 months to 18 years). Nineteen patients belonged to the high‐risk group. Cough was the most common initial symptom, followed by fever. In most patients, serum levels of C‐reactive protein and lactate dehydrogenase were elevated. Oseltamivir, an antiviral agent, was administered to 29 patients. The most common causes of death were encephalopathy and myocarditis, with a higher mortality rate in the high‐risk group. Platelet counts were significantly lower than normal and serum aspartate aminotransferase levels significantly higher in the non‐survivors.ConclusionsThe results of this study suggest that Korean high‐risk pediatric patients have an elevated mortality rate following infection with novel influenza A (H1N1) virus. Further studies involving high‐risk pediatric patients classified using consistent criteria are needed to confirm our results. Pediatr Pulmonol. 2010; 45:1014–1020. © 2010 Wiley‐Liss, Inc.
Bistable defects in low‐energy electron irradiated n‐type 4H‐SiC
Authors: Beyer F. C. , Hemmingsson C. G. , Pedersen H. , Henry A. , Isoya J. , Morishita N. , Ohshima T. , Janzén E. 
Published: July 2010

AbstractEpitaxial n‐type 4H‐SiC layers were irradiated at room temperature by low‐energy electrons. During the annihilation process of the irradiation induced defects EH1 and EH3, three new bistable centers, labeled EB centers, were detected in the DLTS spectrum. The reconfigurations of the EB centers (I → II and II → I) take place at room temperature with a thermal reconfiguration energy of about 0.95 eV. The threshold energy for moving the Si atom from its site in the SiC crystal structure is higher than the applied irradiation energy; therefore, the EB centers are attributed to carbon related complex defects. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Chloride‐based CVD of 3C‐SiC epitaxial layers on 6H(0001) SiC
Authors: Leone Stefano , Beyer Franziska C. , Henry Anne , Kordina Olof , Janzén Erik 
Published: July 2010

AbstractThe heteroepitaxial growth of 3C‐SiC on 6H‐SiC(0001) on‐axis substrates is demonstrated in this study. A hot‐wall CVD reactor working at a reduced pressure was used to perform growth experiments at temperatures between 1300 °C and 1500 °C. The addition of hydrogen chloride to standard precursors allowed a wide window of operating parameters, which resulted in the growth of very high quality and purity 3C‐SiC layers, with a morphology characterized largely by single‐domains, especially when nitrogen was intentionally added. Growth rate of 10 µm/h and n‐type background doping in the low 1015 cm–3 range were achieved. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sparse graphs: Metrics and random models
Authors: Bollobás Béla , Riordan Oliver 
Published: July 2010

AbstractRecently, Bollobás, Janson and Riordan introduced a family of random graph models producing inhomogeneous graphs with n vertices and Θ(n) edges whose distribution is characterized by a kernel, i.e., a symmetric measurable function κ: [0, 1]2 → [0, ∞). To understand these models, we should like to know when different kernels κ give rise to “similar” graphs, and, given a real‐world network, how “similar” is it to a typical graph G(n, κ) derived from a given kernel κ.The analogous questions for dense graphs, with Θ(n2) edges, are answered by recent results of Borgs, Chayes, Lovász, Sós, Szegedy and Vesztergombi, who showed that several natural metrics on graphs are equivalent, and moreover that any sequence of graphs converges in each metric to a graphon, i.e., a kernel taking values in [0, 1].Possible generalizations of these results to graphs with o(n2) but ω(n) edges are discussed in a companion article [Bollobás and Riordan, London Math Soc Lecture Note Series 365 (2009), 211–287]; here we focus only on graphs with Θ(n) edges, which turn out to be much harder to handle. Many new phenomena occur, and there are a host of plausible metrics to consider; many of these metrics suggest new random graph models and vice versa. © 2010 Wiley Periodicals, Inc. Random Struct. Alg., 39, 1‐38, 2011
Electronic and optical properties of La‐aluminate dielectric thin films on Si (100)
Authors: Tahir Dahlang , Choi Eun Hye , Cho Young Joon , Oh Suhk Kun , Kang Hee Jae , Jin Hua , Heo Sung , Chung Jae Gwan , Lee Jae Cheol , Tougaard Sven 
Published: July 2010

AbstractElectronic and optical properties of (La2O3)x(Al2O3)1−x thin films grown on Si(100) by the atomic layer deposition method were studied by means of reflection electron energy loss spectroscopy (REELS). The dielectric function ε(k, ω), index of refraction (n) and the extinction coefficient (k) for (La2O3)x(Al2O3)1−x thin films were obtained from a quantitative analysis of REELS data. The band gap of (La2O3)x(Al2O3)1−x thin films increases from 5.75 to 6.35 eV as the Al2O3 content (1 − x) increases from 0.5 to 0.75 in the compound. The optical properties described in terms of n, k, and ε of (La2O3)x(Al2O3)1−x were obtained from REELS spectra by using QUEELS‐ε(k, ω)‐REELS software. They show that the electronic and optical properties of (La2O3)x(Al2O3)1−x thin films are dominated by La2O3 even for high Al2O3 concentrations. Copyright © 2010 John Wiley & Sons, Ltd.
TOF‐SIMS studies of intercalated Gibbsite and Bayerite
Authors: Nguyen Chuong L. , Perander Linus M. , Hyland Margaret M. , Metson James B. 
Published: July 2010

AbstractSurface studies of the oxides and hydroxides of aluminum by TOF‐SIMS have raised the question of the origin of large fragment ions observed in these spectra at masses well beyond 2000 Daltons. The larger fragment ions, especially in the negative secondary ion spectra, are simple net singly charged (based on stoichiometry) combinations of Al, O and OH.To investigate the origin of these fragments, the layered aluminum hydroxide Gibbsite has been modified to induce changes in interlayer bonding. A base‐hydrolyzed solution of FeCl3 was used to induce intercalation between the Al/O octahedral layers of the Gibbsite structure and the effects of modification were examined in the TOF‐SIMS spectra. The spectra of Fe‐modified Gibbsite are dominated by two major families of (Al2O3)xOH− and (Al2O3)xAlO2− fragments, while those of the unmodified material exhibit additional intermediate fragments attributed to the sampling of multiple octahedral layers. The intercalation of Fe2O3 also causes morphological and structural changes to the Gibbsite particles. Similar modification of another layered aluminum hydroxide, Bayerite, grown on metal surfaces, also removes these intermediate groups, but introduces new iron‐based families of repeating fragments. These studies indicate the repeating fragments observed in the SIMS spectra are sensitive to modification of interlayer bonding in these structures. Copyright © 2010 John Wiley & Sons, Ltd.
Investigation of a connector electrical failure
Authors: Arrowsmith Peter , Kapadia Prakash , Hawley Al , Sodhi Rana 
Published: July 2010

AbstractA PC product built by Celestica experienced a high rate of functional failure. Failure was associated with the CPU and CPU connector (known as a zero insertion force, ZIF type) since mechanically flexing the CPU stack induced failure. This problem became particularly serious when the customer adopted an uncontrolled (manual) “press” test, resulting in a large amount of rejected product which may have been functional under normal operating conditions.A failure analysis method involving static loading the CPU and epoxy potting the connector stack was developed to mechanically “trap” the fail condition. Sectioning and electrical probing was used to determine which of the 240 active connector pins have high resistance.Analysis of suspect connector pins and contact surfaces pointed to several possible causes of failure. SEM‐EDX revealed localized damage to the Au plating with exposed Ni and NiO. XPS and TOF‐SIMS with depth profiling confirmed the presence of a ∼100 nm layer of a fluorocarbon on the Au surface. Although it was not possible to clearly locate the individual electrical contact spots (1–10 µm diameter) to identify localized contamination, the presence of a probable insulating coating was sufficient evidence to follow‐up with the connector supplier. The connector spring contacts were found to be coated with an “anti‐flux” agent to prevent wicking of liquid solder onto contact surfaces during the wave solder assembly process. The corrective action was to change the ZIF connector to a type without anti‐flux coating and the failure rate was significantly reduced. Copyright © 2010 John Wiley & Sons, Ltd.
Composition optimization and UV‐annealing dependence on the electrical properties of Hf1−xSixO2/Si gate stacks
Authors: He G. , Zhang L. D. , Liu M. , Fang Q 
Published: July 2010

AbstractHf1−xSixO2 gate dielectrics grown by UV‐photo‐induced chemical vapor deposition (UV‐CVD) using Hf(OBut)2(mmp)2 and tetraethoxysilane as precursors have been deposited on Si substrate. Composition dependence of the interfacial microstructure of the Hf1−xSixO2/Si gate stacks has been investigated via Fourier transform infrared spectroscopy (FTIR) systematically. It has been indicated that the physical properties of the Hf1−xSixO2 films can be effectively optimized by adjusting the silicon contents incorporated in the films. In order to evaluate its potential implementation as an alternative dielectric in future devices, detailed electrical characterization of Au/Hf1−xSixO2/Si capacitor has been performed as functions of the silicon contents and the UV‐annealing time. Copyright © 2010 John Wiley & Sons, Ltd.
IP address assignment in wireless mesh networks
Authors: Zimmermann Alexander , Hannemann Arnd , Schleinzer Benjamin 
Published: July 2010

AbstractIn recent years cheap Internet access has become increasingly popular within the industrialized countries. Especially in the age of Web 2.0, where popular Internet applications begin to dominate computer use, ubiquitous network access is more important than ever. A new class of networks aim to satisfy the demand for high bandwidth, low‐cost, and ubiquitous Internet access: wireless mesh networks (WMNs). However, in order to reach a greater market penetration a fundamental factor must yet to be addressed: the ease of use. Except for small networks, manual configuration is infeasible, so robust autoconfiguration mechanisms are needed. To address this shortcoming of complicated setup procedures we introduce and evaluate a novel autoconfiguration protocol for WMN: the Dynamic WMN Configuration Protocol (DWCP). It deals with the assignment of unique addresses, the management of free and assigned addresses, the autonomous reaction to failures, and features support of conventional Dynamic Host Configuration Protocol (DHCP) clients. It is specifically suitable for large installations and was deployed and evaluated in a real testbed. Copyright © 2010 John Wiley & Sons, Ltd.