bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cathodic Electrografting of Versatile Ligands on Si(100) as a Low‐Impact Approach for Establishing a SiC Bond: A Surface‐Coordination Study of Substituted 2,2′‐Bipyridines with CuI Ions
Authors: Aurora Annalisa , Cattaruzza Fabrizio , Coluzza Carlo , Della Volpe Claudio , Di Santo Giovanni , Flamini Alberto , Mangano Carlo , Morpurgo Simone , Pallavicini Piersandro , Zanoni Robertino 
Published: October 2006

AbstractThree distinct wet chemistry recipes were applied to hydrogen‐terminated n‐ and p‐Si(100) surfaces in a comparative study of the covalent grafting of two differently substituted 2,2′‐bipyridines. The applied reactions require the use of heat, or visible light under a controlled atmosphere, or a suitable potential in an electrochemical cell. In this last case, hydrogen‐terminated silicon is the working electrode in a cathodic electrografting (CEG) reaction, in which it is kept under reduction conditions. The resulting SiC bound hybrids were characterized by a combination of AFM, dynamic contact‐angle, and XPS analysis, with the help of theoretical calculations. The three distinct approaches were found to be suitable for obtaining ligand‐functionalized Si surfaces. CEG resulted in the most satisfactory anchoring procedure, because of its better correlation between high coverage and preservation of the Si surface from both oxidation and contamination. The corresponding Si–bipyridine hybrid was reacted in a solution of CH3CN containing CuI ions coordinatively bound to the anchored ligands, as evidenced from the XPS binding‐energy shift of the N atom donor functions. The reaction gave a 1:2 Cu–bipyridine surface complex, in which two ligands couple to a single CuI ion. The surface complex was characterized by the Cu Auger parameter and Cu/N XPS atomic‐ratio values coincident with those for pure, unsupported CuI complex with the same 2,2′‐bipyridine. Further support for such a specific metal–ligand interaction at the functionalized Si surface came from the distinct values of Cu2p binding energy and the Cu Auger parameter, which were obtained for the species resulting from CuI ion uptake on hydrogen‐terminated Si(100).
Cover Picture: Stereoselective Glycosylations Using (R)‐ or (S)‐(Ethoxycarbonyl)benzyl Chiral Auxiliaries at C‐2 of Glycopyranosyl Donors (Eur. J. Org. Chem. 22/2006)
Authors: Kim Jin‐Hwan , Yang Hai , Khot Vishal , Whitfield Dennis , Boons Geert‐Jan 
Published: October 2006

AbstractThe cover picture shows the proposed mechanistic pathway for the stereoselective glycosylation based on Density Functional Theory calculations of the model compound. The protected sugar that has a chiral protecting group that is derived from mandelic acid and is attached to O‐2 after activation to an oxacarbenium ion species can form energetically favorable 6‐membered‐ring dioxolenium ions. The favored dioxolenium ion has the phenyl substituent in an equatorial position in both cases, allowing for the chirality of the protecting group to be transferred to the stereochemistry of the synthetically isolated glycoside. Details are discussed in the article by D. Whitfield, G.‐J. Boons et al. on p. 5007 ff.
Prediction of fire classification for wood based products. A multivariate statistical approach based on the cone calorimeter
Authors: Steen‐Hansen Anne , Kristoffersen Bjarne 
Published: October 2006

AbstractWood has long traditions as a building material, and is often used in construction elements, and as interior and exterior surfaces in the Nordic countries. In most applications, there are reaction to fire requirements to products used as surfaces, e.g. in escape routes and larger public spaces. Most wood products will therefore have to be treated with fire retardant (FR) agents to fulfil the strict requirements to properties connected to heat release and flame spread. Unfortunately, FR agents usually also increase the smoke production, as they cause a more incomplete combustion of the wood. The wood product manufacturers seek to find the optimal amount of FR additives where both heat release and smoke production in the classifying test are within the requirements given in the building regulations. This paper describes models for prediction of the European reaction to fire classes of wood products. The models are based on multivariate statistical analysis, and use test results from the cone calorimeter test as input. The presented models are, with very good precision, able to predict which Euroclass and additional smoke class a wood based product would obtain if it were to be tested in the single burning item test. Copyright © 2006 John Wiley & Sons, Ltd.
Reconstruction of an arson hospital fire
Authors: Hertzberg Tommy , Blomqvist Per , Tuovinen Heimo 
Published: October 2006

AbstractAn arson fire in a Swedish psychiatric detention clinic led to the death of two patients and injuries to many more. Rescue personnel were quick to go into the building on fire but had difficulties finding their way due to a very heavy smoke. The reconstruction made, indicates that a too easily ignitable mattress provided heat and radiation enough to ignite a PVC flooring material that then became the main source for fire and smoke. Analysis of soot from the fire site and measurements during the reconstruction show that the fire smoke contained large amounts of irritants that might have had an impact on the tragic outcome. In fact, comparing the toxicity of smoke gases produced during the reconstruction, based on different ‘toxicity indicators’, suggests that irritants in the fire smoke were as dangerous as or even more dangerous than the common asphyxiate type of gases present, CO and HCN.Another suggestion from the reported work is that the importance of flooring material for enclosure fire development might be overlooked. The reconstruction clearly demonstrates that the tragic fire would not have happened if the requirements for the flooring material had been the same as for the walls and ceiling materials. Copyright © 2006 John Wiley & Sons, Ltd.
Manganese(II) and iron(II) derivatives of tris{(diphenylphosphino)dimethylsilyl}methane: Synthesis and properties
Authors: Gupta Sushil K. , Kelkar Anoop 
Published: October 2006

AbstractTreatment of anhydrous MCl2 (M = Mn, Fe) with (Ph2PMe2Si)3CH in toluene at elevated temperature resulted in the isolation of colorless (MnCl2{(Ph2PMe2Si)3CH}) (1) and light yellow (FeCl2{(Ph2PMe2Si)3CH}) (2) in high yield. These paramagnetic complexes have been characterized by elemental analyses, magnetic moment, conductivity measurements, TGA, cyclic voltammetry, mass spectrometry, with IR, electronic, ESR and Mössbauer spectroscopy. The data suggest that complexes 1 and 2 have trigonal bipyramidal geometry around the metal atom with tridentate coordination of the ligand. The thermal stability of the Fe(II) complex 2 is greater than that of the Mn(II) compound 1. Electrochemical studies of complex 1 and 2 using cyclic voltammetry indicate a quasi‐reversible reduction (E1/2 = ca. −1.08 V (1)) and an irreversible cathodic reduction (Epc, ca. −1.55 V (2)) to Mn(0) and to Fe(0), respectively. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:692–698, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20238
Dynamics of evapotranspiration from a riparian pond complex in the Western Boreal Forest, Alberta, Canada
Authors: Petrone R. M. , Silins U. , Devito K. J. 
Published: October 2006

AbstractThe relative contributions to total actual evapotranspiration (AET) from pond and riparian areas in a pond‐wetland complex in the Western Boreal Plain (WBP) of northern Alberta are measured using the Bowen ratio energy balance technique. Measurements show that a pond typical of the WBP evaporates at a rate more than twice that of the adjacent riparian peatland. Relating the actual to potential evapotranspiration over both surfaces yields Priestley–Taylor α coefficients of 0·69 and 1·11 for the peatland and pond respectively. Further results demonstrate that the sheltering and turbulent influences of the adjacent forested areas must be considered in the processes governing the permanence of WBP ponds. That is, forestry practices may inadvertently enhance the evaporative losses from the ponds, over and above the controls exerted by the regional climate. Copyright © 2006 John Wiley & Sons, Ltd.
Is Palaeospondylus gunni a fossil larval lungfish? Insights from Neoceratodus forsteri development
Authors: Joss Jean , Johanson Zerina 
Published: October 2006

AbstractThe enigmatic Devonian fossil Palaeospondylus gunni was identified as a larval form, metamorphosing into the lungfish Dipterus valenciennesi. Morphological features used to identify P. gunni as a larval lungfish include enlarged cranial ribs, rudimentary limb girdles, and absence of teeth. However, this combination of features does not characterize the extant lungfish Neoceratodus forsteri, even at very young stages, nor early stages of Devonian and younger fossil lungfish. Absence of teeth is problematic because early ontogenetic stages of fossil and living lungfish possess full dentitions including marginal teeth. Also problematic are cranial ribs as a defining character of lungfish, as these also occur in certain actinopterygians.It is argued that Neoceratodus is an obligate neotene (reproductively mature larva), with the implication that metamorphosis was a feature of the ontogeny of early lungfish. Pedomorphic characters have been recognized in Neoceratodus and other post‐Devonian lungfish, including large cells and correspondingly large genome size; these latter characters correlate with neoteny in salamanders. Small cells preserved in fossil bone suggest that Devonian lungfish had a smaller genome than post‐Devonian lungfish, implying that they were not neotenic. As fossil lungfish cell sizes (and genomes) increased in the late Paleozoic, the diversity of lungfish morphologies decreased, so that taxa like Sagenodus and Conchopoma show morphological similarity to Neoceratodus, marking a point in phylogeny at which metamorphosis was potentially lost. Since ancestral larval characters are retained in neotenic adults, we predict that Devonian larvae should resemble these post‐Devonian taxa, a prediction which Palaeospondylus does not fulfill. J. Exp. Zool. (Mol. Dev. Evol.) 306B, 2006. © 2006 Wiley‐Liss, Inc.
Physical activity modulates nerve plasticity and stimulates repair after achilles tendon rupture
Authors: Bring Daniel K‐I. , Kreicbergs Andris , Renstrom Per A.F.H. , Ackermann Paul W. 
Published: October 2006

AbstractIn a rat model of tendon rupture using semiquantitative methodology, healing was assessed according to the diameter of newly organized collagen and the occurrence of the sensory neuropeptides (SP, CGRP) in relation to different levels of physical activity. Normally, innervation of the Achilles tendon is confined to the paratenon. After rupture new nerve fibers grow into the tendon proper, but disappear after healing. In a first experiment to establish peak tissue and nerve regeneration after rupture, tendon tissues from freely moving rats were collected consecutively over 16 weeks. A peak increase in organized collagen and nerve ingrowth was observed between week 2 to 4 post rupture. Therefore, in a second experiment week 4 was chosen to assess the effect of physical activity on tendon healing in three groups of rats, that is, wheel running, plaster treated, and freely moving (controls). In the wheel‐running group, the diameter of newly organized collagen was 94% ( p = 0.001) greater than that in the plaster‐treated group and 48% ( p = 0.02) greater than that in the controls. Inversely, the neuronal occurrence of CGRP in the tendon proper was 57% ( p = 0.02) lower in the wheel‐running group than that in the plaster‐treated group and 53% ( p = 0.02) lower than that in the controls, suggesting an earlier neuronal in‐growth and disappearance in the more active group. Physical activity speeds up tendon healing, which may prove to be linked to accelerated neuronal plasticity. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:164–172, 2007
Novel Dynamic Viscoelastic Measurements of Polyurethane Copolymer Melts and Their Implication to Tack Results
Authors: Florez Sonia , Muñoz María Eugenia , Santamaría Anton 
Published: October 2006

AbstractSummary: A series of polyurethane multiblock copolymers with different proportions of hard segments (urethane) to soft segments (polyadipate of hexane‐1,6‐diol), are investigated. Dynamic viscoelastic functions of homogeneous melts in the terminal zone are determined. For the first time, entanglement modulus values of such copolymers are reported, which allows estimation of the packing length. These parameters do not vary with changing the hard‐to‐soft segment ratio, a result that is explained by a compensating effect of the chain architecture. For samples of similar molecular weight, the relaxation time of the terminal zone increases as the hard‐to‐soft segment ratio augments. The adhesives obtained from PUR solutions show a correlation between the elastic modulus and the debonding stress‐strain curves in tack experiments.The storage modulus of the adhesives as a function of frequency at 70 °C.magnified imageThe storage modulus of the adhesives as a function of frequency at 70 °C.
Physico‐Mechanical Properties, Odor and VOC Emission of Bio‐Flour‐Filled Poly(propylene) Bio‐Composites with Different Volcanic Pozzolan Contents
Authors: Kim Hee‐Soo , Kim Sumin , Kim Hyun‐Joong , Kim Hak‐Gyeom 
Published: October 2006

AbstractSummary: This study investigated the physico‐mechanical properties, odor and VOC emission of bio‐flour filled PP bio‐composites with different pozzolan contents. On increasing the pozzolan content, the tensile and flexural strengths of the bio‐composites were not significantly changed, whereas the impact strength and water absorption increased slightly and the odor intensity decreased due to the absorption of thermal degradation gases of PP and bio‐flour at the pore surface of the pozzolan. The VOC emission of the bio‐composites, analyzed by GC‐MSD, was mainly due to PP oxidation and the thermal degradation of bio‐flour during the extrusion process at high manufacturing temperatures. With increased pozzolan content, other organic compounds of the bio‐composites were not significantly changed, but the toluene emission of the bio‐composites was decreased. SEM and SEM/EDX mapping techniques were employed to investigate the porous form and the pozzolan distribution in the bio‐composites. From these results, we concluded that the addition of pozzolan in the bio‐composites was an effective method for reducing their odor and VOC emission without any reduction in mechanical properties.SEM micrograph of pozzolan (10 000×).magnified imageSEM micrograph of pozzolan (10 000×).
Unexpected Crosslinking During Acetoacetoxy Group Protection on Waterborne Crosslinkable Latexes
Authors: González Iñigo , Arzamendi Gurutze , Asua José M. , Leiza José R. 
Published: October 2006

AbstractSummary: The microstructure of the polymer synthesized by seeded semicontinuous emulsion copolymerization of AAEMA was investigated. It was found that the neutralization of the latexes with ammonia to protect acetoacetoxy functionality against hydrolysis during storage had a remarkable effect on the gel content. A base catalyzed Michael addition reaction between acetoacetoxy groups and terminal double bond (TDB) is proposed as responsible for the chain precrosslinking observed. The presence of TDB in the latexes was demonstrated by means of 1H NMR. Moreover, the chain precrosslinking affected the subsequent crosslinking reaction of the latex with diamines hindering chain interdiffusion and yielding poorer mechanical properties.Michael addition between AcAc functional groups and TDB, and final gel content of the MMA/BA/MAA latexes with different amounts of AAEMA.magnified imageMichael addition between AcAc functional groups and TDB, and final gel content of the MMA/BA/MAA latexes with different amounts of AAEMA.
Unusual clinical, laboratory, and muscle histopathological findings in a family with myotonic dystrophy type 2
Authors: Toth Cory , Dunham Chris , Suchowersky Oksana , Parboosingh Jillian , Brownell Keith 
Published: October 2006

AbstractMyotonic dystrophy type 2 (DM2) is a multisystem degenerative disorder with distinctive clinical and electrophysiological features. Recently, genetic confirmation has become available with the identification of the molecular defect, an expansion of a CCTG repeat located in intron 1 of the zinc finger protein 9 (ZNF9) gene. We present two first‐degree relatives with an athletic clinical phenotype, pathological evidence of subsarcolemmal vacuolation, and molecular genetic confirmation of DM2. When found in the proper clinical context, athleticism and pathological subsarcolemmal vacuoles should not dissuade the clinician from the possible diagnosis of DM2. Muscle Nerve, 2006
Water‐soluble polymer materials as complexing reagents for the separation of metal ions using membrane filtration
Authors: Rivas Bernabé L. , Pooley S. Amalia , Pereira Eduardo , Montoya Erika , Cid Rocío , Geckeler Kurt E. 
Published: October 2006

AbstractThe commercial, water‐soluble poly(sodium anetole sulfonate) (PAnS), poly(sodium vinylsulfonate) (PVS), and poly(sodium 4‐styrene sulfonate) (PStyS) were investigated as metal ion binding reagents using the liquid‐phase‐polymer‐based retention (LPR) technique. The retention profiles of the following metal ions: Co(II), Ni(II), Ca(II), Mg(II), Pb(II), Cd(II), Zn(II), Cr(III), and Cu(II) were obtained by the LPR technique at pH 3, 5, and 7, and by changing the filtration factor Z from 0 to 10. As the pH increased, the affinity towards the metal ions increased slightly. By increasing the filtration factor Z, the affinity for the metal ions did not decrease significantly. This means that the ligand–metal interaction was strong, and it is not possible to break it by washing with water at the same pH of the filtration cell. Copyright © 2006 John Wiley & Sons, Ltd.
Crystal structure of human dual specificity phosphatase, JNK stimulatory phosphatase‐1, at 1.5 Å resolution
Authors: Yokota Takehiro , Nara Yukinori , Kashima Akiko , Matsubara Keiko , Misawa Satoru , Kato Ryohei , Sugio Shigetoshi 
Published: October 2006

AbstractHuman JNK stimulatory phosphatase‐1 (JSP‐1) is a novel member of dual specificity phosphatases. A C‐terminus truncated JSP‐1 was expressed in Escherichia coli and was crystallized using the sitting‐drop vapor diffusion method. Thin‐plate crystals obtained at 278 K belong to a monoclinic space group, C2, with unit‐cell parameters a = 84.0 Å, b = 49.3 Å, c = 47.3 Å, and β = 119.5°, and diffract up to 1.5 Å resolution at 100 K. The structure of JSP‐1 has a single compact (α/β) domain, which consists of six α‐helices and five β‐strands, and shows a conserved structural scaffold in regard to both DSPs and PTPs. A cleft formed by a PTP‐loop at the active site is very shallow, and is occupied by one sulfonate compound, MES, at the bottom. In the binary complex structure of JSP‐1 with MES, the conformations of three important segments in regard to the catalytic mechanism are not similar to those in PTP1B. JSP‐1 has no loop corresponding to the Lys120‐loop of PTP1B, and tryptophan residue corresponding to the substrate‐stacking in PTP1B is substituted by alanine residue in JSP‐1. Proteins 2007. © 2006 Wiley‐Liss, Inc.
Reactivity of Biologically Important NSAID Compounds with Superoxide (O2.−), nitric oxide (.NO) and Cyclooxygenase Inhibition
Authors: Pérez Carmen , Sánchez Juan , Mármol Federico , Puig‐Parellada Pere , Pouplana Ramon 
Published: October 2006

AbstractIn the present study, we investigated the free radical‐scavenging effects of eight Nonsteroidal Anti‐Inflammatory Drugs (NSAID) using a Superoxide (O2.−) and Nitric Oxide (.NO) generating system in vitro. Indomethacine showed higher scavenging activity against O2.−, it being more potent than ibuprofen and nimesulide at the same concentration. Diclofenac showed a more relevant effect on the .NO scavenging activity than against O2.−. Comparison of the activities of eight compounds showed that the aryl‐acetic compounds have higher scavenging activities than the diarylheterocyclic ones. We have also found that the O2 scavenging activity correlates with the Next‐Highest‐Occupied π‐Orbital (NHOMO) levels and the Next‐Lowest‐Unoccupied π‐Orbital (NLUMO)‐NHOMO gaps correlate with Cyclooxygenase‐1 (COX‐1) inhibitory activity. These results suggest that both NHOMO and NHOMO‐NLUMO gap energies can be of predictive value in the search for new candidate anti‐inflammatory drugs.
Theoretical study of spectroscopic constants and molecular properties of rare‐gas diatomic cations
Authors: Bera N. C. , Bhattacharyya I. , Das A. K. 
Published: October 2006

AbstractAb initio and density functional methods are applied to study the spectroscopic constants and molecular properties of the diatomic cations He, Ne, Ar, HeNe+, and HeAr+. Among these cations, HeAr+ is found to be weakly bound and its spectroscopic constants are calculated using the Lennard‐Jones potential. The other molecules that are strongly bound obey Morse potential, and their spectroscopic constants are calculated accordingly. The calculated spectroscopic constants agree very well with the theoretical and experimental values wherever available. Most of the spectroscopic constants and molecular properties are reported for the first time. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Theoretical study of the Si2NO potential energy surface
Authors: Yu Guang‐Tao , Huang Xu‐Ri , Ding Yi‐Hong , Chen Wei , Sun Chia‐Chung 
Published: October 2006

AbstractThe structures, spectroscopies, and stabilities of the doublet Si2NO radical are explored at the density functional theory (DFT) and ab initio levels. Seventeen isomers are located, connected by 26 interconversion transition states. At the CCSD(T)/6‐311+G(2df)//QCISD/6‐311G(d)+ZPVE level, three low‐lying isomers are predicted, that is, one bent species SiNSiO 3 (5.1 kcal/mol) containing the important SiN triple bonding and two four‐membered ring isomers including cyclic cSiNSiO 1 (0.0) with SiSi cross‐bonding with C2v symmetry and puckered cSiNSiO 1′ (11.9) with divalent carbene character. Three low‐lying isomers 1, 1′, and 3 have reasonable kinetic stabilities and might be observable either experimentally or astrophysically. The possible formation strategies of 1, 1′, and 3 in laboratory and in space are discussed in detail. The calculated vibrational frequencies and possible formation processes of 3 are consistent with recent experimental observations. In light of the fact that no cyclic nitrogen‐containing species have been detected in space, two cyclic isomers 1 and 1′ could be promising candidates. Furthermore, the bonding nature of three isomers 1, 1′, and 3 is analyzed. The calculated results are also compared with those of the analogue C2NO radical. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Global convergence for two-pulse rest-to-rest learning for single-degree-of-freedom systems with stick-slip Coulomb friction
Authors: Driessen Brian J. , Sadegh Nader 
Published: October 2006

SUMMARYIn this paper, we consider the problem of rest-to-rest maneu-ver learning, via iterative learning control (ILC), for single-degree-of-freedom systems with stick-slip Coulomb friction and input bounds. The static coefficient of friction is allowed to be as large as three times the kinetic coefficient of friction. The input is restricted to be a two-pulse one. The desired input's first pulse magnitude is required to be five times the largest possible kinetic (sliding) friction force. The theory therefore allows the stiction force to be as large as the desired second input pulse. Under these conditions, we prove global convergence of a simple iterative learning controller. To the best of our knowledge, such a global-convergence proof has not been presented previously in the literature for the rest-to-rest problem with stick-slip Coulomb friction.