bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accurate prediction of basicity in aqueous solution with COSMO‐RS
Authors: Eckert Frank , Klamt Andreas 
Published: October 2005

AbstractThe COSMO‐RS method, a combination of the quantum chemical dielectric continuum solvation model COSMO with a statistical thermodynamics treatment for realistic solvation simulations, has been used for the prediction of base pKa constants. For a variety of 43 organic bases the directly calculated values of the free energies of dissociation in water showed a very good correlation with experimental base pKa values (r2 = 0.98), corresponding to a standard deviation of 0.56 pKa units. Thus, we have an a priori prediction method for base pKa with the regression constant and the slope as only adjusted parameters. In accord with recent findings for pKa acidity predictions, the slope of pKa vs. ΔGdiss was significantly smaller than the theoretically expected value of 1/RTln(10). The predictivity of the presented method is general and not restricted to certain compound classes, but systematic corrections of 1 and 2 pKa units for secondary and tertiary aliphatic amines are required, respectively. The pKa prediction method was validated on a set of 58 complex multifunctional drug‐like compounds, yielding an RMS accuracy of 0.66 pKa units. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 11–19, 2006
Studies in transesterification of ethylene carbonate to dimethyl carbonate over Amberlyst A‐21 catalyst
Authors: Dhuri Shekhar M , Mahajani Vijaykumar V 
Published: October 2005

AbstractTransesterification of ethylene carbonate (EC) with methanol (MeOH) was studied in a slurry reactor using various homogeneous and heterogeneous, acidic as well as basic, catalysts. Among all catalysts studied, the weakly basic anion‐exchange resin Amberlyst A‐21 gave more than 95% selectivity towards dimethyl carbonate (based on EC converted). Using this Amberlyst A‐21 as a catalyst, the kinetics for the transesterification reaction was studied in the range of temperature from 363 to 393 K, varying catalyst loading from 11.24 to 44.97 kg m−3 and the molar ratio MeOH:EC being varied between 4:1 and 16:1. The initial rate data were analysed using a power law model to aid process design. Copyright © 2005 Society of Chemical Industry
Biological and electrochemical oxidation of naphthalenesulfonates
Authors: Panizza Marco , Zolezzi Marcello , Nicolella Cristiano 
Published: October 2005

AbstractA biofilm airlift suspension (BAS) reactor and an undivided flow cell equipped with a boron‐doped diamond (BDD) anode and a stainless‐steel cathode were used to investigate the effects of varying operating conditions on process performance in the biological and electrochemical oxidation of a mixture of naphthalenesulfonates contained in the infiltration water of a contaminated industrial site. The experiments were aimed at evaluating the feasibility of process integration and the criteria for optimization (i.e. how to maximize degradation efficiency with minimum energy consumption) in combined biological and electrochemical oxidation of scarcely biodegradable compounds. Because of high reactor biomass concentration and long biomass retention time, the BAS reactor achieved a high degradation capacity (up to 6.8 kg COD m−3 d−1). On the other hand, owing to the recalcitrant character of some of the aromatic sulfonates in the leachate, the overall degradation efficiency did not exceed 70% based on COD measurements. All naphthalene‐mono‐ and ‐disulfonates (except naphthalene‐1,5‐disulfonate) were completely degraded in the BAS reactor, whereas more complex molecules (e.g. naphthalenetrisulfonates) were more recalcitrant to biological oxidation. These compounds were completely mineralized by electrochemical oxidation using a boron‐doped diamond anode. The energy consumption and the time required for the complete mineralization of the infiltration water decreased from 80 kWh m−3 and 4 h to 61 kWh m−3 and 3 h for the oxidation of raw and biologically pretreated leachate, respectively. Copyright © 2005 Society of Chemical Industry
Revised capillary suction time (CST) test to reduce consumable costs and improve dewaterability interpretation
Authors: Scholz Miklas 
Published: October 2005

AbstractThe aim of this paper is to critically assess the standard capillary suction time (CST) test and to propose a modified device (prototype) and a revised CST procedure. The empirical CST test (using a circular funnel) is well established as the leading method for the determination of sludge dewaterability in spite of its current shortcomings such as restricted modelling possibilities, and therefore the ability to predict physical processes such as the amount of water bound by the paper. Nevertheless, the CST apparatus is portable, and the method is easy to conduct, quick, cost‐effective and accurate, if the product of solid concentration and average specific resistance to filtration is of interest. A novel prototype with a rectangular instead of a circular funnel incorporating a stirrer (optional), and using a cheaper paper with similar or improved characteristics is proposed to reduce consumable costs and improve dewaterability interpretation. Copyright © 2005 Society of Chemical Industry
The ligand effect in Ti‐mediated living radical styrene polymerizations initiated by epoxide radical ring opening. 1. Alkoxide and bisketonate Ti complexes
Authors: Asandei Alexandru D. , Moran Isaac W. 
Published: October 2005

AbstractBisketonate and alkoxide Ti(III) complexes derived from Zn reduction of Ti(IV) precursors were evaluated as catalysts for the living radical polymerization (LRP) of styrene initiated by Ti‐catalyzed epoxide radical ring opening and mediated by reversible termination with Ti(III). No polymerization occurred with tris(2,2,6, 6‐tetramethyl‐3,5‐heptanedionato)titanium (III), whereas dichlorobis(2,2,6,6‐tetramethyl‐3,5‐heptanedionato)titanium (IV) affords only a free radical polymerization. Preliminary living features were displayed by (iPrO)2TiCl2. Investigations of the effect of epoxide/Ti/Zn ratios, temperature, and nature of the epoxide demonstrated that (iPrO)3TiCl provides a linear dependence of Mn on conversion over a wide range of conditions with an optimum for [Sty]/[epoxide group]/[Ti]/[Zn] = 50/1/2/4 at 90 °C. However, the polydispersity could not be reduced below 1.4–1.5, with an initiator efficiency of 0.15. These results were rationalized in terms of a combination of decreased Ti oxophilicity and ligand exchange. The lowered oxophilicity decreases the initiation rate and broadens Mw/Mn. The fast alkoxide exchange promotes a weak dependence of the polymerization on reaction conditions and generates macromolecular Ti species with reduced ability to mediate LRP. Thus, while monofunctional epoxides provide homogeneous polymerizations and narrower Mw/Mn, difunctional initiators may lead to gel formation at high conversion. Nonetheless, all polymerizations were light gray to colorless and afforded white polymer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6028–6038, 2005
Synthesis and characterization of multifunctional polymers via atom transfer radical polymerization of N‐(ω′‐alkylcarbazolyl) methacrylates initiated by Ru(II) polypyridyl chromophores
Authors: Farah Abdiaziz A. , Pietro William J. 
Published: October 2005

AbstractA series of poly(N‐(ω′‐alkylcarbazoly) methacrylates) tris(bipyridine) Ru‐centered bifunctional polymers with good filming, thermal, and solubility properties were synthesized and characterized. Atom transfer radical polymerization (ATRP) of N‐(ω′‐alkylcarbazoly) methacrylates in solution was used, where Ru complexes with one and three initiating sites acted as metalloinitiators with NiBr2(PPh3)2 as a catalyst. ATRP reaction conditions with respect to polymer molecular weights and polydispersity indices (PDI) of the target bifunctional polymers were examined. Electronic absorption and emission spectra of the resultant functional polymers provided evidence of chromophore presence within a single polymeric chain. The thermal properties of all polymers were also investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and these analyses have indicated that these polymers possess higher thermal stabilities than poly(methyl methacrylate) (PMMA) obtained via free radical polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6057–6072, 2005
Flame‐retardant epoxy resins with high glass‐transition temperatures. II. Using a novel hexafunctional curing agent: 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene 10‐yl‐tris(4‐aminophenyl) methane
Authors: Lin Ching Hsuan , Cai Sheng Xiong , Lin Chun Hung 
Published: October 2005

AbstractWe synthesized a novel phosphorus‐containing triamine [9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene 10‐yl‐tris(4‐aminophenyl) methane (dopo‐ta)] from the nucleophilic addition of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene 10‐oxide and pararosaniline chloride, using triethylamine as an acid receiver. We confirmed the structure of dopo‐ta by IR, mass, and NMR spectra and elemental analysis. dopo‐ta served as a curing agent for diglycidyl ether of bisphenol A (DGEBA) and dicyclopentadiene epoxy (hp7200). Properties such as the glass‐transition temperature (Tg), thermal decomposition temperature, flame retardancy, moisture absorption, and dielectric properties of the cured epoxy resins were evaluated. The Tg's of cured DGEBA/dopo‐ta and hp7200/dopo‐ta were 171 and 190 °C, respectively. This high Tg phenomenon is rarely seen in the literature after the introduction of a flame‐retardant element. The flame retardancy increased with the phosphorus content, and a UL‐94 V‐0 grade was achieved with a phosphorus content of 1.80 wt % for DGEBA/dopo‐ta/diamino diphenylmethane (DDM) systems and 1.46 wt % for hp7200/dopo‐ta/DDM systems. The dielectric constants for DGEBA/dopo‐ta and hp7200/dopo‐ta were 2.91 and 2.82, respectively, implying that the dopo‐ta curing systems exhibited low dielectric properties. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5971–5986, 2005
Synthesis of sequence‐controlled copolymers from extremely polar and apolar monomers by living radical polymerization and their phase‐separated structures
Authors: Inoue Yuuki , Watanabe Junji , Takai Madoka , Yusa Shin‐ichi , Ishihara Kazuhiko 
Published: October 2005

AbstractA series of copolymers composed of two monomer units having a polar phosphorylcholine group and an apolar fluorocarbon group with a controlled monomer unit sequence were synthesized by a reversible addition‐fragmentation chain transfer (RAFT) living radical polymerization method. 2‐Methacryloyloxyethyl phosphorylcholine (MPC) and 2,2,2‐trifluoroethyl methacrylate (TFEMA) were selected as the monomers, because they have disparate polarity. Furthermore, to investigate the influence of the monomer unit sequence in a polymer chain on the phase‐separated structure in the bulk and surface structure, copolymers having a continuous change in the monomer unit composition along the polymer chain (gradient copolymer) were synthesized, as well as random and block copolymers. The analysis of instantaneous composition revealed a continuous change in the monomer unit composition in the gradient copolymer and the statistical monomer unit sequence in the random copolymer. Thermal analysis assumed that the gradient sequence of the monomer unit would make the phase‐separated structure in the bulk ambiguous, while the well‐defined and monodispersive block sequence would undergo the distinct phase‐separation due to the extreme difference in the polarity of the component monomer units. The preliminary surface characterization of the synthesized polymers indicated the monomer unit sequence in the polymer chain would much influence on the surface structure. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6073–6083, 2005
Acyclic diene metathesis polymerization of 2,5‐dialkyl‐1,4‐divinylbenzene with molybdenum or ruthenium catalysts: Factors affecting the precise synthesis of defect‐free, high‐molecular‐weight trans‐poly(p‐phenylene vinylene)s
Authors: Nomura Kotohiro , Miyamoto Yoshitaka , Morimoto Hisao , Geerts Yves 
Published: October 2005

AbstractFactors affecting the syntheses of high‐molecular‐weight poly(2,5‐dialkyl‐1,4‐phenylene vinylene) by the acyclic diene metathesis polymerization of 2,5‐dialkyl‐1,4‐divinylbenzenes [alkyl = n‐octyl (2) and 2‐ethylhexyl (3)] with a molybdenum or ruthenium catalyst were explored. The polymerizations of 2 by Mo(N‐2,6‐Me2C6H3) (CHMe2 Ph)[OCMe(CF3)2]2 at 25 °C was completed with both a high initial monomer concentration and reduced pressure, affording poly(p‐phenylene vinylene)s with low polydispersity index values (number‐average molecular weight = 3.3–3.65 × 103 by gel permeation chromatography vs polystyrene standards, weight‐average molecular weight/number‐average molecular weight = 1.1–1.2), but the polymerization of 3 was not completed under the same conditions. The synthesis of structurally regular (all‐trans), defect‐free, high‐molecular‐weight 2‐ethylhexyl substituted poly(p‐phenylene vinylene)s [poly3; degree of monomer repeating unit (DPn) = ca. 16–70 by 1H NMR] with unimodal molecular weight distributions (number‐average molecular weight = 8.30–36.3 × 103 by gel permeation chromatography, weight‐average molecular weight/number‐average molecular weight = 1.6–2.1) and with defined polymer chain ends (as a vinyl group, CHCH2) was achieved when Ru(CHPh)(Cl)2(IMesH2)(PCy3) or Ru(CH‐2‐OiPr‐C6H4)(Cl)2(IMesH2) [IMesH2 = 1,3‐bis(2,4,6‐trimethylphenyl)‐2‐imidazolidinylidene] was employed as a catalyst at 50 °C. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6166–6177, 2005
Molecular mobility of free‐radical‐functionalized carbon‐nanotube/siloxane/poly(urea urethane) nanocomposites
Authors: Wu Han‐Lang , Yang Yu‐Ting , Ma Chen‐Chi M. , Kuan Hsu‐Chiang 
Published: October 2005

AbstractMultiwalled carbon nanotubes (MWNTs) were functionalized by a free‐radical reaction of vinyltriethoxysilane and were blended with poly(urea urethane) (PUU) containing poly(dimethylsiloxane) as a soft segment. PUU was end‐capped with aminopropyltriethoxysilane (A‐silane) or phenyltriethoxysilane (P‐silane).A‐silane‐end‐capped PUU was covalently bonded to functionalized MWNTs, whereas P‐silane‐end‐capped PUU was noncovalently bonded to pristine MWNTs by a π–π interaction. Fourier transform infrared, Raman spectra, and thermogravimetric analysis confirmed the functionalization of MWNTs. The results showed that the optimal reaction time of the functionalization of MWNT was 8 h, and the organic content of the modified carbon nanotubes reached 35.22%. Solid‐state nuclear magnetic resonance and dynamic mechanical analysis were used to investigate the molecular structure and molecular mobility of the carbon‐nanotube/PUU nanocomposites. A‐silane PUU covalently bonded to MWNTs showed a considerable reduction in the molecular motion of the soft segment, which led to the glass‐transition temperature decreasing from −117 to −127 °C as MWNTs were incorporated. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6084–6094, 2005
A new reversed‐phase liquid chromatographic/tandem mass spectrometric method for analysis of underivatised amino acids: evaluation for the diagnosis and the management of inherited disorders of amino acid metabolism
Authors: Piraud M. , Vianey‐Saban C. , Bourdin C. , Acquaviva‐Bourdain C. , Boyer S. , Elfakir C. , Bouchu D. 
Published: October 2005

AbstractSeventy‐six compounds of biological interest for the diagnosis of inherited disorders of amino acids (AA) metabolism have previously been demonstrated to be detectable in positive mode electrospray ionisation tandem mass spectrometry (ESI‐MS/MS), after separation by ion‐pairing reversed‐phase liquid chromatography (RPLC). The separation method used tridecafluoroheptanoic acid as ion‐pairing agent, and a gradient of acetonitrile for the elution of the most retained compounds. This method had previously been demonstrated to be suitable for the qualitative diagnosis of many AA disorders, and for the quantitative measurement of 16 AA in biological fluids, using their stable isotope labelled (SIL) AA as internal standard. For quantification of the other AA, an internal standard was chosen among the available SIL‐AA, as close as possible to the analyte to be measured, in terms of structural analogy, and of retention time in the chromatographic system. The performances of the quantitative analysis of the other AA to be measured are reported here. They show validated results for several AA, allowing their accurate quantification, with another SIL‐AA as internal standard. For some other AA, quantitative results were not accurate, allowing only semi‐quantitative or qualitative determination for these parameters. Copyright © 2005 John Wiley & Sons, Ltd.
Confident protein identification using the average peptide score method coupled with search‐specific, ab initio thresholds
Authors: Shadforth Ian , Dunkley Tom , Lilley Kathryn , Crowther Daniel , Bessant Conrad 
Published: October 2005

AbstractPerhaps the greatest difficulty in interpreting large sets of protein identifications derived from mass spectrometric methods is whether or not to trust the results. For such experiments, the level of confidence in each protein identification made needs to be far greater than the often used 95% significance threshold to avoid the identification of many false‐positives. To provide higher confidence results, we have developed an innovative scoring strategy coupling the recently published Average Peptide Score (APS) method with pre‐filtering of peptide identifications, using a simple peptide quality filter. Iterative generation of these filters in conjunction with reversed database searching is used to determine the correct levels at which the APS and peptide quality thresholds should be set to return virtually zero false‐positive reports. This proceeds without the need to reference a known dataset. Copyright © 2005 John Wiley & Sons, Ltd.
Clinical deterioration in established heart failure: What is the value of BNP and weight gain in aiding diagnosis?
Authors: Lewin Jennifer , Ledwidge Mark , O'Loughlin Christina , McNally Clare , McDonald Ken 
Published: October 2005

AbstractBackground:Weight gain and increase in B‐Type Natriuretic Peptide have been advocated as means of aiding diagnosis of heart failure. However, there are few data to support the use of these criteria in diagnosing clinical deterioration in patients with established disease.Aims:This prospective study examines the sensitivity and specificity of absolute and relative changes in BNP and weight in determining the early onset of clinical deterioration in patients with established heart failure.Methods:All patients who presented to the outpatient clinic with completed self‐reported daily weight books, baseline BNP measurement, outpatient BNP measurement and assessment by a cardiologist blinded to BNP and weight were included. Each patient was determined as clinically stable (CS) or in clinical deterioration (CD). Receiver operating characteristic (ROC) curves and sensitivity and specificity calculations for various absolute and relative BNP and weight changes were carried out.Results:Weight and BNP changes were examined in 34 CS presentations (mean age 69.5±16.1 years) and 43 CD presentations (mean age 70.0±10.6 years). ROC analysis demonstrated that neither weight nor BNP changes in absolute or relative values predicted clinical deterioration in this study population adequately (AUC values ranging from 0.64 to 0.66).Conclusions:These data demonstrate that increase in body weight and BNP in isolation are not sensitive in assessing clinical deterioration in established heart failure. These observations may need to be emphasized in patient education and to physicians involved in assessment of heart failure patients.
On the phenology of North Sea ichthyoplankton
Authors: Greve Wulf , Prinage Sabine , Zidowitz Heike , Nast Jutta , Reiners Frank 
Published: October 2005

Abstract
The timing of fish larvae abundance was investigated at Helgoland Roads in the southern North Sea for the years 1990, 1993–1996, 1998, and 1999. From the 44 species identified, 27 were sufficiently abundant in more than 3 years and had well defined seasonal changes to calculate their phenology. The passage of the 15%, 50%, and 85% annual cumulative abundance thresholds was used to define the “start of season”, “middle of season”, and “end of season”, respectively. The timing of a significant number of these events was correlated with the mean annual winter sea surface temperatures (SSTs) in weeks 1–10 with higher temperatures leading to earlier appearance. The timing of the end of season was also negatively correlated with the SSTs. Sole (Solea solea) is presented as an example of the general functional relationship.
Long-term variability of growth and recruitment of cod (Gadus morhua) off Greenland
Authors: Rätz Hans-Joachim , Lloret Josep 
Published: October 2005

Abstract
Growth variation was estimated from mean lengths-at-ages 4 and 5 for Atlantic cod off Greenland based on 52 973 fish taken from commercial and scientific catches from 1955 to 2002. Mean length-at-age values were corrected for area and seasonal effects, and significant growth reductions occurred during the 1960s and from the mid-1970s until the mid-1980s. Annual growth rates of cod in Greenland waters during the most recent decade (1993–2002) were consistently among the highest recorded. Statistical growth models accounting for temperature, fishing mortality, and stock abundance effects were constructed. Multiple linear regressions revealed significant positive temperature effects on growth of both age groups and a significant negative stock density effect on length-at-age 4. Correlations between exploitation intensity and length-at-age were statistically insignificant. During the period 1955–2002, the number of recruits at age 3 was significantly correlated with the Greenland cod spawning-stock biomass, June water temperature on top of Fyllas Bank (West Greenland), and Iceland cod recruitment. All factors had a positive effect on the number of Greenland recruits and, combined, accounted for 60% of the observed variation. Spawning stock size was, by far, the most important factor contributing to recruitment variability, while June water temperature below 1°C and Iceland recruits below 150 million never coincided with high year-class strength in Greenland during the past 50 years. Thus, previous conclusions regarding a close relation between the Greenland and Icelandic cod stocks might need to be reconsidered in the light of a continued recruitment failure in Greenland waters over the two most recent decades, despite the improved environmental conditions and near-average recruitment of the Icelandic stock. The low precision of the recruitment model, however, prevents reliable predictions in the short or medium term, but a substantial short-term recovery of the Greenland cod stock remains unlikely.
Acetylcholinesterase activity in hosts (herring Clupea harengus) and parasites (Anisakis simplex larvae) from the southern Baltic
Authors: Podolska Magdalena , Napierska Dorota 
Published: October 2005

Abstract
This study compares the acetylcholinesterase (AChE) activity of herring Clupea harengus infected with Anisakis simplex larvae and non-infected individuals caught in coastal waters of the southern Baltic. Acetylcholinesterase activity was measured spectrophotometrically. Generalized linear models were applied to analyse the dependence of AChE activity on the area of sampling and the biological parameters of fish and their parasites. The AChE activity of herring was higher in samples from the western and central coasts (regarded as “clean” waters) than in fish caught in the semi-enclosed areas of the Gulf of Gdańsk and Vistula Lagoon (regarded as “polluted” sites). The opposite relationship was noted in the activity of AChE extracted from A. simplex larvae. In male hosts, the parasitic AChE activity was markedly higher than in the females in all examined areas.