bluuebunny/crossref_metadata_2025_split huggingface dataset:
CASTA DIVA®: Experiments and Modeling of Oxide-Induced Deformation in Nuclear Components
Authors: Barberis P. , Rebeyrolle V. , Vermoyal J. J. , Chabretou V. , Vassault J. P. 
Published: May 2008

Abstract
In-pile deformation of nuclear structural components remains a major preoccupation for fuel vendors and utilities, especially when introducing new alloys or extending burn-ups. The usual invoked causes of such deformations are free growth, hydriding (hydrides induce a volume expansion which translates into deformation), irradiation creep if the component is subjected to external loads (e.g., axial load for the fuel assembly), and flux gradients (for fuel channel bow). In this paper we show through out-of-pile experiments (autoclave corrosion and low temperature air oxidation) and in-pile data analysis that the oxide layer significantly contributes to the deformation. A model (CASTA DIVA®) taking into account all the above mentioned phenomena has been derived and correctly predicts the deformation behavior, the stresses in the oxide layer, as well as the external cracking of the oxide. The relative impacts of hydriding and stresses in the metal are computed. A comparison between Zircaloy-4 and M5® is made, showing the better behavior of M5.
Solderability Testing of Lead-Free Solder Joints Using Miniature Specimens
Authors: Rosenthal Y. , Sabag O. , Tourgeman A. , Zalkind S. , Stern A. , Eliezer D. 
Published: May 2008

Abstract
A new method for mechanical testing of lead-free solder joints solderability is presented. Copper blanks are soldered with a known thermal cycle. Miniature tensile solder joints specimens are produced in large numbers from the blanks having a gage section made of lead-free solder alloy with dimensions that represent actual solder joints. Mechanical properties of Sn-3.5Ag-0.7Cu in tension at room temperature and strain-rates between 2.8×10−4–2.7×10−1s−1 have been studied. It is concluded that the solder section of the miniature joints is the weakest link in this complex structure. It was also found that the experimental results for solder strength and strain-rate sensitivity are in partial agreement with data obtained using solder bulk specimens. The role of microstructure across the joint, especially intermetallic compounds along the copper/solder interface is also discussed.
The Very‐Low Shear Modulus of Multi‐Walled Carbon Nanotubes Determined Simultaneously with the Axial Young's Modulus via in situ Experiments
Authors: Wei Xian‐Long , Liu Yang , Chen Qing , Wang Ming‐Sheng , Peng Lian‐Mao 
Published: May 2008

AbstractThe natural frequencies (f) as a function of the length (L) of single, multi‐walled carbon nanotubes (CNTs) are measured using the electric‐field‐induced resonance method together with the “nanoknife” technique for cutting nanotubes to the desired length. The experimental f‐L data for short CNTs are found to be adequately described by the Timoshenko beam model, but not by the widely‐used Euler‐Bernouilli beam model. The failure of the Euler‐Bernouilli beam model is due to its neglect of the significant effect of shear deformation caused by the extremely‐anisotropic mechanical properties of CNTs. The axial Young's modulus and radial shear modulus of CNTs are obtained simultaneously through fitting the experimental f‐L data with the Timoshenko beam model.
Functionalized Asymmetric Linear Acenes for High‐Performance Organic Semiconductors
Authors: Tang Ming L. , Reichardt Anna D. , Okamoto Toshihiro , Miyaki Nobuyuki , Bao Zhenan 
Published: May 2008

AbstractA series of compounds from the tetraceno[2,3‐b]thiophene and the anthra[2,3‐b]thiophene family of semiconducting molecules has been made. Specifically, synthetic routes to functionalize the parent molecules with bromo and then hexyl groups are shown. The bromo‐ and hexyl‐functionalized tetraceno[2,3‐b]thiophene and anthra[2,3‐b]thiophene were characterized in the top‐contact thin‐film transistor (TFT) geometry. They give high mobilities, ranging from 0.12 cm2 V−1 s−1 for α‐n‐hexylanthra[2,3‐ b]thiophene to as high as 0.85 cm2 V−1 s−1 for α‐bromotetraceno[2,3‐b]thiophene. Notably, grain size increases, going from the shorter anthra[2,3‐b]thiophene core to the longer tetraceno[2,3‐b]thiophene core, with a corresponding increase in mobility. The transition from undesirable 3D to desirable 2D thin‐film growth is explained by the increase in length of the molecule, in this case by one benzene ring, which results in an increase in intralayer interactions relative to interlayer interactions.
Developments in Nanostructured Cathode Materials for High‐Performance Lithium‐Ion Batteries
Authors: Wang Ying , Cao Guozhong 
Published: May 2008

AbstractNanostructured materials lie at the heart of fundamental advances in efficient energy storage and/or conversion, in which surface processes and transport kinetics play determining roles. This Review describes some recent developments in the synthesis and characterization of nanostructured cathode materials, including lithium transition metal oxides, vanadium oxides, manganese oxides, lithium phosphates, and various nanostructured composites. The major goal of this Review is to highlight some new progress in using these nanostructured materials as cathodes to develop lithium batteries with high energy density, high rate capability, and excellent cycling stability resulting from their huge surface area, short distance for mass and charge transport, and freedom for volume change in nanostructured materials.
Relatedness in wild chimpanzees: Influence of paternity, male philopatry, and demographic factors
Authors: Inoue Eiji , Inoue‐Murayama Miho , Vigilant Linda , Takenaka Osamu , Nishida Toshisada 
Published: May 2008

AbstractIn chimpanzees (Pan troglodytes), high‐ranking males are expected to have high reproductive success and females typically emigrate upon reaching maturity. Although high average relatedness among males in the same social groups has been assumed, previous reports have indicated that relatedness among males is not necessarily significantly higher than that among females. The paternity of 11 offspring and the relatedness of 50 individuals in the M group of chimpanzees at Mahale Mountains National Park, Tanzania, were investigated using DNA analyses. We determined the fathers of 10 offspring. Two different alpha males sired a total of five offspring, whereas the other males had low reproductive success. The proportion of paternal half‐sibling pairs among the 10 offspring was 15.6%. The average relatedness among mature males was significantly higher than that among mature females. The existence of an old male and the long tenure of one alpha male may have contributed to this significant difference. The average dyadic relatedness among mature natal individuals was significantly higher than that in natal‐immigrant pairs in which the individuals came from different groups. The average relatedness among immigrant females was similar to that in pairs of natal and immigrant females, suggesting that the immigrants came from various groups. Thus, female transfer acts to maintain low average relatedness within the group. A comparison of our results to those from other study sites suggests that although the average relatedness among adult males does not reach the level of half‐siblings, under some circumstances it can exceed the relatedness of females. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.
Adsorption of Cu2+ ions with poly(N‐isopropylacrylamide‐co‐methacrylic acid) micro/nanoparticles
Authors: Wu Qinglin , Tian Peng 
Published: May 2008

AbstractChelation efficiency of stimuli‐responsive poly(N‐iospropylacrylamide‐co‐methyacrylic acid) (PNIPAAm‐MAA) nanoparticles with Cu2+ ions from CuSO4·5H2O solution and from wood treated with copper‐based preservatives was studied. It was shown that particle size played a very important role in the adsorption process. The nano‐scale particles showed much improved Cu ion adsorption efficiency, compared with the micro hydrogels. The amount of Cu ion adsorption increased with increase of MAA ratio in copolymers and adsorption efficiency decreased with increased particle size. Furthermore, the adsorption amount varied with adsorption temperature at temperatures both below and above the corresponding low critical solution temperature (LCST). The high adsorption efficiency of Cu ions by PNIPAAm‐MAA polymer particles provides an effective technique for recovering metal ions (e.g., Cu2+) from wood treated with metal‐based preservatives. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Influence of DC conductivity of PPy anode on Li/PPy secondary batteries
Authors: Ren Li , Su Liwei , Chen Xiaofeng 
Published: May 2008

AbstractPolypyrrole(PPy) was first synthesized by chemical oxidative polymerization. Then the assembling of cells was made by using PPy as anode and the lithium cathode. Its electrochemical properties were tested using galvanostatic system. The influences of DC conductivity of PPy anode on Li/PPy secondary batteries were mainly studied. The results showed when using high conductivity PPy as anode active material, the doping–undoping of the anions was easy and the discharge capacity of the cell was high, after fifty cycles the coulombic efficiency was 99.2%, the electrochemical stability and cycling property were still good. From condensed matter physics, the doping manner of conducting PPy was explained. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Findings of extensive variation in the types of outcome measures used in hip and knee replacement clinical trials: A systematic review
Authors: Riddle Daniel L. , Stratford Paul W. , Bowman Dixie H. 
Published: May 2008

AbstractObjectiveTo describe the extent of variation in outcome measure usage in hip and knee replacement randomized trial literature, and to summarize this variation in the context of the International Classification of Functioning, Disability, and Health (ICF) conceptual model created by the World Health Organization (WHO).MethodsWe used a defined search strategy in Medline and EMBase databases to identify articles published from January 2000 to February 2007. Studies were reviewed if they were randomized trials with a ≥6‐week followup and if they used noninvasive outcome measures of impaired joint function or whole‐person limitations in daily activities or functional status. The WHO ICF model was used to categorize outcome measures.ResultsOf 972 studies, 160 were included for review. Of these, 82 were conducted on patients with hip replacements, 75 on patients with knee replacements, and 3 on patients with both. The most common outcome measure in knee trials was the American Knee Society score (used in 48% of reviewed studies), and in hip trials was the Harris hip score (52.4%). At least 20 different outcome measures were used in the hip trials, and at least 14 different measures were used in knee trials. The primary outcome was identified in only 24% of trials.ConclusionWe found extensive variation in outcome measures across trials and saw inconsistency across the components of the WHO ICF model. To improve interpretability, future work should determine whether consensus can be developed for a standardized set of outcome measures for hip and knee replacement trials.
α,α‐Diarylprolinol Ethers: New Tools for Functionalization of Carbonyl Compounds
Authors: Mielgo Antonia , Palomo Claudio 
Published: May 2008

Abstractα,α‐Diaryl(dialkyl)prolinol ethers constitute a potent organocatalyst family which has been shown to be very general for a broad range of reactions involving enamine and iminium ion activation or a combination of both. The reactions are characterized by an efficient steric control approach and can lead to a variety of α‐, β‐, γ‐, and α,β‐functionalized carbonyl compounds with excellent stereocontrol. As a full expression of their catalytic activity, these compounds are also excellent promoters of elegant cascade processes and valuable catalysts in water‐compatible systems.
The effect of high strength static magnetic fields and ionizing radiation on gene expression and DNA damage in Caenorhabditis elegans
Authors: Kimura Takafumi , Takahashi Kohki , Suzuki Yoko , Konishi Yukinaga , Ota Yuta , Mori Chihiro , Ikenaga Takahiko , Takanami Takako , Saito Rumiko , Ichiishi Eiichiro , Awaji Satoshi , Watanabe Kazuo , Higashitani Atsushi 
Published: May 2008

AbstractMagnetic resonance imaging with high static magnetic fields (SMFs) has become widely used for medical imaging purposes because SMFs cause fewer genotoxic side effects than ionizing radiation (IR). However, the effect of exposure to high SMFs on global transcription is little understood. We demonstrate that genes involved in motor activity, actin binding, cell adhesion, and cuticles are transiently and specifically induced following exposure to 3 or 5 T SMF in the experimental model metazoan Caenorhabditis elegans. In addition, transient induction of hsp12 family genes was observed after SMF exposure. The small‐heat shock protein gene hsp16 was also induced but to a much lesser extent, and the LacZ‐stained population of hsp‐16.1::lacZ transgenic worms did not significantly increase after exposure to SMFs with or without a second stressor, mild heat shock. Several genes encoding apoptotic cell‐death activators and secreted surface proteins were upregulated after IR, but were not induced by SMFs. Real‐time quantitative RT‐PCR analyses for 12 of these genes confirmed these expression differences between worms exposed to SMFs and IR. In contrast to IR, exposure to high SMFs did not induce DNA double‐strand breaks or germline cell apoptosis during meiosis. These results suggest that the response of C. elegans to high SMFs is unique and capable of adjustment during long exposure, and that this treatment may be less hazardous than other therapeutic tools. Bioelectromagnetics 29:605–614, 2008. © 2008 Wiley‐Liss, Inc.
Exposure of seeds to static magnetic field enhances germination and early growth characteristics in chickpea (Cicer arietinum L.)
Authors: Vashisth Ananta , Nagarajan Shantha 
Published: May 2008

AbstractSeeds of chickpea (Cicer arietinum L.) were exposed in batches to static magnetic fields of strength from 0 to 250 mT in steps of 50 mT for 1–4 h in steps of 1 h for all fields. Results showed that magnetic field application enhanced seed performance in terms of laboratory germination, speed of germination, seedling length and seedling dry weight significantly compared to unexposed control. However, the response varied with field strength and duration of exposure without any particular trend. Among the various combinations of field strength and duration, 50 mT for 2 h, 100 mT for 1 h and 150 mT for 2 h exposures gave best results. Exposure of seeds to these three magnetic fields improved seed coat membrane integrity as it reduced the electrical conductivity of seed leachate. In soil, seeds exposed to these three treatments produced significantly increased seedling dry weights of 1‐month‐old plants. The root characteristics of the plants showed dramatic increase in root length, root surface area and root volume. The improved functional root parameters suggest that magnetically treated chickpea seeds may perform better under rainfed (un‐irrigated) conditions where there is a restrictive soil moisture regime. Bioelectromagnetics 29:571–578, 2008. © 2008 Wiley‐Liss, Inc.
Electrochemically Protected Copper(I)‐Catalyzed Azide–Alkyne Cycloaddition
Authors: Hong Vu , Udit Andrew K. , Evans Richard A. , Finn M. G. 
Published: May 2008

AbstractThe copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) reaction has found broad application in myriad fields. For the most demanding applications that require high yields at low substrate concentrations, highly active but air‐sensitive copper complexes must be used. We describe here the use of an electrochemical potential to maintain catalysts in the active CuI oxidation state in the presence of air. This simple procedure efficiently achieves excellent yields of CuAAC products from both small‐molecule and protein substrates without the use of potentially damaging chemical reducing agents. A new water‐soluble carboxylated version of the popular tris(benzyltriazolylmethyl)amine (TBTA) ligand is also described. Cyclic voltammetry revealed reversible or quasi‐reversible electrochemical redox behavior of copper complexes of the TBTA derivative (2; E1/2=60 mV vs. Ag/AgCl), sulfonated bathophenanthroline (3; E1/2=−60 mV), and sulfonated tris(benzimidazoylmethyl)amine (4; E1/2≈−70 mV), and showed catalytic turnover to be rapid relative to the voltammetry time scale. Under the influence of a −200 mV potential that was established by using a reticulated vitreous carbon working electrode, CuSO4 and 3 formed a superior catalyst. Electrochemically protected bioconjugations in air were performed by using bacteriophage Qβ that was derivatized with azide moieties at surface lysine residues. Complete derivatization of more than 600 reactive sites per particle was demonstrated within 12 h of electrolysis with substoichiometric quantities of Cu⋅3.
Edge‐to‐Face CH/π Aromatic Interaction and Molecular Self‐Recognition in epi‐Cinchona‐Based Bifunctional Thiourea Organocatalysis
Authors: Tárkányi Gábor , Király Péter , Varga Szilárd , Vakulya Benedek , Soós Tibor 
Published: May 2008

AbstractThe impact of cooperativity between intermolecular interactions is demonstrated by the molecular self‐recognition properties of highly enantioselective epi‐cinchona bifunctional thiourea organocatalysts. Low‐temperature NMR experiments in inert solvents have revealed two sets of nonequivalent resonances in equal population for thiourea‐modified members of the epi‐quinine and epi‐quinidine families. In solution, the predominance of an asymmetric (C1) dimeric self‐assembly with noteworthy structural motifs became evident: simultaneous intra‐ and intermolecular thiourea hydrogen bonding and a CH/π interaction were observed. Both the stereochemical and the diverse conformational features of the system favor the observed quinoline T‐shaped aromatic π–π stacking interaction. The structure findings are supported by quantitative proton–proton distance data that were available from NOE buildup curves. The 3D structure of the dimeric assembly has been modeled in agreement with the H–H distance restraints. Owing to the geometrical preference associated with the dimerization process, the self‐assembled bifunctional system is interpreted as a charge‐transfer complex with the potential for catalyst self‐activation.
PGSE NMR Diffusion Overhauser Studies on [Ru(Cp*)(η6‐arene)][PF6], Plus a Variety of Transition‐Metal, Inorganic, and Organic Salts: An Overview of Ion Pairing in Dichloromethane
Authors: Moreno Aitor , Pregosin Paul S. , Veiros Luis F. , Albinati Alberto , Rizzato Silvia 
Published: May 2008

AbstractPGSE diffusion, 19F, 1H HOESY and 13C NMR studies for a series of [Ru(Cp*)(η6‐arene)][PF6] (1) salts are presented. The solid‐state structure of [Ru(Cp*)(η6‐fluorobenzene)][PF6] (1 c) is reported. The extent of the ion pairing and the relative positions of the ions are shown to depend on the arene. For the solvent dichloromethane, new and literature PGSE data for PF6− salts of transition‐metal, inorganic, and organic salts are compared. Taken together, these new results show that the charge distribution and the ability of the anion to approach the positively charged positions (steric effects due to molecular shape) are the determining factors in deciding the amount of ion pairing. DFT calculations of the charges in four salts of type 1, as well as in a variety of other salts, using a natural population analysis (NPA), support this view. This represents the first attempt, using experimental data, to understand, correlate, and partially explain the various degrees of ion pairing in a widely different collection of salts.
Reactions of Nitroheteroarenes with Carbanions: Bridging Aromatic, Heteroaromatic, and Vinylic Electrophilicity
Authors: Seeliger Florian , Błażej Sylwia , Bernhardt Sebastian , Mąkosza Mieczysław , Mayr Herbert 
Published: May 2008

AbstractThe relative rate constants for the vicarious nucleophilic substitution (VNS) of the anion of chloromethyl phenyl sulfone (1−) with a variety of nitroheteroarenes, for example, nitropyridines, nitropyrroles, nitroimidazoles, 2‐nitrothiophene, and 4‐nitropyrazole, have been determined by competition experiments. It was shown that nitropyridines are approximately four orders of magnitude more reactive than nitrobenzene. Among the five‐membered heterocycles 2‐nitrothiophene is the most active followed by nitroimidazoles and 4‐nitropyrazole. Nitropyrroles are the least electrophilic nitroheteroarenes with reactivities comparable to nitrobenzene. Quantum chemically calculated methyl anion affinities (B3LYP/6–311G(d,p)//B3LYP/6–31G(d)) of the nitroarenes correlated only moderately with the partial relative rate constants. The correlation of these activities with the LUMO energies of nitroarenes is even worse. By measuring the second‐order rate constants of the addition of 1− to nitroarenes and to diethyl arylidenemalonates 10, it was possible to link the electrophilic reactivities of nitroheteroarenes with the comprehensive electrophilicity scale based on the linear‐free‐energy‐relationship log k(20 °C)=s(N + E).
The First Silicon‐Based Cationic Clathrate III with High Thermal Stability: Si172−xPxTey (x=2y, y>20)
Authors: Zaikina Julia V. , Kovnir Kirill A. , Haarmann Frank , Schnelle Walter , Burkhardt Ulrich , Borrmann Horst , Schwarz Ulrich , Grin Yuri , Shevelkov Andrei V. 
Published: May 2008

AbstractA new representative of a very rare clathrate III family, Si130P42Te21, has been synthesized from the elements. It crystallizes in the tetragonal space group P42/mnm (no. 136) with the unit cell parameters a=19.2632(3) Å, c=10.0706(2) Å. Single crystal X‐ray diffraction and solid state 31P NMR revealed a non‐random distribution of phosphorus atoms over the framework positions. The crystal structure features a peculiar packing of large polyhedra Te@(Si/P)n never observed before for cationic clathrates. Despite the structural complexity, the composition of the novel clathrate Is in accordance with the Zintl rule, which was confirmed by a combination of optical metallography, scanning electron microscopy (SEM) and wavelength dispersive X‐ray spectroscopy (WDXS), as well as by diamagnetic and semiconducting behavior of the synthesized phase. Clathrate Si130P42Te21 exhibits the highest reported thermal stability for this class of materials, it decomposes at 1510 K. This opens new perspectives for the creation of clathrate‐based materials for high‐temperature applications.
Supramolecular Synthons on Surfaces: Controlling Dimensionality and Periodicity of Tetraarylporphyrin Assemblies by the Interplay of Cyano and Alkoxy Substituents
Authors: Wintjes Nikolai , Hornung Jens , Lobo‐Checa Jorge , Voigt Tobias , Samuely Tomáš , Thilgen Carlo , Stöhr Meike , Diederich François , Jung Thomas A. 
Published: May 2008

AbstractThe self‐assembly of three porphyrin derivatives was studied in detail on a Cu(111) substrate by means of scanning tunneling microscopy (STM). All derivatives have two 4‐cyanophenyl substituents in diagonally opposed meso‐positions of the porphyrin core, but differ in the nature of the other two meso‐alkoxyphenyl substituents. At coverages below 0.8 monolayers, two derivatives form molecular chains, which evolve into nanoporous networks at higher coverages. The third derivative self‐assembles directly into a nanoporous network without showing a one‐dimensional phase. The pore‐to‐pore distances for the three networks depend on the size and shape of the alkoxy substituents. All observed effects are explained by 1) different steric demands of the alkoxy residues, 2) apolar (mainly dispersion) interactions between the alkoxy chains, 3) polar bonding involving both cyanophenyl and alkoxyphenyl substituents, and 4) the entropy/enthalpy balance of the network formation.