bluuebunny/crossref_metadata_2025_split huggingface dataset:
Auswirkungen einer Temperaturerhöhung in einem Freilandexperiment auf den Stickstoffaustrag aus Bodensäulen mit verschiedenartiger Humusform
Authors: Kolb Eckart , Rehfuess Karl E. 
Published: February 2007

AbstractEine Klimaerwärmung könnte die Eigenschaften von Böden nach‐haltig verändern. Nach dem bisherigen Kenntnisstand ist zu erwarten, daß ein Temperaturanstieg unter sonst vergleichbaren Bedingungen zu einer Abnahme der Stickstoffvorräte bis zur Einstellung eines neuen Gleichgewichtes führt. Zu dieser Arbeitshypothese legten wir in den Tegernseer Alpen ein Freilandexperiment an. In fichtenreichen Bergmischwäldern wurden insgesamt 60 ungestörte Bodenblöcke (= Monolithe) in 1250 bzw. 1320 m über NN sorgfätlig ausgegraben und entlang eines Gebirgshanges auf 1250, 1010 und 740 m über NN wieder bodengleich eingebaut, um so einen durchschnittlichen Temperaturanstieg von ca. +1 bzw. +2°C zu simulieren. Dabei verglichen wir die beiden sauren Bodenformen Rohhumus‐Braunerde (RH) aus Reiselsberger Sandstein und tonreiche Moder‐Braunerde (MO) aus Quarziten und Mergeln des Flysch‐Gault. Jedes der 6 Prüfglieder war mit 10 Monolithen vertreten. In 2‐ bis 4‐wöchigen Abständen entnahmen wir von August 1992 bis Dezember 1995 mittels Saugkerzen Sickerwasserproben und analysierten sie auf alle wichtigen Bioelemente ein‐schließlich Aluminium sowie pH und elektrische Leitfähigkeit. Aus beiden Bodenformen wurde nach Erwärmung von ca. 1 bzw. 2°C vermehrt Stickstoff überwiegend als Nitrat freigesetzt. Dabei reagierte die Moder‐Braunerde mit der umsatzaktiveren Humusform stärker als die Braunerde mit Rohhumus (Mehraustrag > 40 vs. 34 kg ha−1 a−1 bei +2°C). In beiden Bodenformen war die Nitratauswaschung im Sommer beschleunigt, und zwar in der Rohhumus‐Braunerde um durchschnittlich 55 auf 92 ppm (RH) bzw. um 37 auf 86 ppm (MO) bei +2°C. MO setzte aber Stickstoff vermehrt auch im Winter frei und erreichte so einen insgesamt höheren N‐Austrag. Al war in allen Fällen mit durchschnittlich 75% (RH) bzw. 54% (MO) Anteil an der Kationen‐Äquivalentsumme das wichtigste Begleitkation von NO3−. Das Experiment belegt somit auch schon bei einem Anstieg der mittleren Jahrestemperatur von nur 1 bis 2°C eine nennenswerte Beschleunigung der Nitrifikation. Sie sollte bei Ausschluß der Vegetation auf durchlässigen Böden zu verstärkter Nitratauswaschung und damit Versauerung führen.
Soil organic matter transformation in Argentinian Hapludolls
Authors: Zech Wolfgang , Guggenberger Georg , Zalba Pablo , Peinemann Norman 
Published: February 2007

AbstractDistribution and transformation of SOM in an Argentinian Hapludoll under arable land use and afforested withPinus radiatawas investigated by a combined approach using particle‐size fractionation, wet‐chemical analysis and13C NMR spectroscopy. The soils showed thick mollic A horizons and had high organic carbon (OC) contents even in the subsoil, clay‐sized separates having the highest OC concentrations. Under pine, a thick forest floor was built up. CuO oxidation data indicated low transformation of lignin in the forest floor, but advanced oxidative decomposition in the mineral soil horizon. In contrast, non‐cellulosic carbohydrates, appeared to be stabilized in the mineral soil horizon against mineralization. Humic acids extracted from the mineral soil horizons showed an extremely high aromaticity. We assume that this was due to the production of pyrogenic aromatic moieties (black carbon) as a result of frequent fires in this ecosystem. No clear profile differentiation with respect to SOM quality was obtained. Composition of SOM in the mineral soil appeared not yet influenced from land use.
Polycyclic Aromatic Hydrocarbons (PAHs) in Forest Floors of the Northern Czech Mountains
Authors: Wilcke Wolfgang , Zech Wolfgang 
Published: February 2007

AbstractForests of the Northern Czech mountains decline due to industrial emissions. To examine the state of soil contamination with PAHs we analyzed the concentrations of 20 PAHs in the O and A horizons of 4 lower and 4 upper slope sites under beech (Fagus sylvatica L.) in the Western (WE) and the Eastern Erzgebirge (EE, Krušné Hory), the Isergebirge (IS, Jizerské Hory), and the Riesengebirge (RI, Krkonoše) at microsites affected and not affected by stem flow. Average PAH sum concentrations in the organic layers ranged between 2000 and 30000 μg kg−1 increasing in the line WE <RI<EE<IS. PAH concentrations were significantly higher at upper than at lower slope sites indicating long‐distance transport. Microsites affected by stem flow had significantly higher PAH concentrations but lower percentages of lower molecular PAHs than microsites not affected by stem flow. This was due to the water collecting effect of the beech bark. Lower molecular PAHs preferentially were sorbed to the bark or leached from the organic layers. PAH concentrations increased from Oi to Oa horizons but decreased in the mineral soil. This was the more pronounced the higher the molecular weight was. The slope of the regression line between the enrichment factors (concentration of a single PAH in the Oa divided by that in the Oi horizon) and the octanol‐water partition coefficient decreased as the PAH concentration of the soils increased. This indicates that the microbial activity of organic layers may be reduced by soil contamination. Cluster analysis suggested that the sources of the PAH contamination in the WE were different from the other sites.
Response of laying Japanese quails to graded levels of essential amino acids profile with reduced dietary protein
Authors: Kaur Sarabmeet , Mandal Asit B , Singh Kunwer B , Kadam Mukund M , Elangovan Arumbackam V 
Published: February 2007

AbstractThe effect on egg production of graded levels of ideal amino acids, combined with reduced protein in the diet, was investigated in 312 laying quails aged 6–18 weeks. The quails were offered six diets, each of which contained one of three levels of amino acids (85, 100 and 115% of essential amino acids (EAAs)) together with 5% or without fishmeal (FM) (3 × 2 factorial design). Each diet was offered to 26 replicated groups of two quails each. Hen‐day and hen‐housed egg production did not differ as a result of EAA level, protein type or their interaction during the overall period of egg production. Egg weight improved linearly (P < 0.01) with increased EAA levels, while egg mass output per bird per day remained similar at the 100 and 115% EAA levels. Quails fed higher (100 and 115%) EAA levels had an improved feed conversion ratio (P < 0.01) compared to birds fed 85% EAA. The gain in body weight during the laying period was higher (P < 0.01) at the 100 or 115% than at 85% EAA levels The ratio of egg mass or egg mass and live weight gain, together, to protein intake improved (P < 0.01) linearly with a decrease in EAA levels in the diets, while better (P < 0.01) energy efficiency (EE, energy intake: egg mass) and net EE (energy intake: egg mass plus gain) was obtained in higher EAA levels (100 or 115%). Protein and energy efficiencies remained similar due to protein type or interaction. Shape index, albumen index, yolk index, yolk colour and relative shell weight did not differ due to EAA levels, protein type or their interaction. Eggs laid from quails fed diets with 100% EAAs without FM and 115% EAAs with or without FM had higher shell thickness than those on 85% EAAs irrespective of protein type. The retention of nitrogen and calcium retention was higher (P < 0.01) at the 115% EAA level. The results indicated a dietary level of 100% EAA (185 g kg−1 crude protein (CP)) with 12.13 MJ kg−1 was suitable for laying quails of 6–18 weeks of age. Copyright © 2007 Society of Chemical Industry
Extreme breeding: Leveraging genomics for crop improvement
Authors: Brady Siobhan M , Provart Nicholas J 
Published: February 2007

AbstractThe genomic revolution has led to dramatic increases in our understanding of plant biology in the past 10 years, especially in model plant species such as Arabidopsis. The technologies associated with this revolution, such as tilling, array mapping, and association mapping, will see widespread application to crop improvement in the near future. The genes for desirable traits identified through such efforts may be introgressed at an accelerated rate into elite germplasm by marker‐assisted breeding. Copyright © 2007 Society of Chemical Industry
Influence of farming conditions on colour and texture of European catfish (Silurus glanis) flesh
Authors: Hallier Arnaud , Chevallier Sylvie , Serot Thierry , Prost Carole 
Published: February 2007

AbstractThe colour of raw fillets and the texture of cooked fillets of European catfish (Silurus glanis) were studied. The catfish fillets resulted from two types of farming conditions used in France. Sensory and instrumental analyses were performed on the fillets. Two farming parameters were found to affect the colour and texture of European catfish fillets: water temperature and farming time. The shorter the farming time was, the lighter the fillets were, while a higher water temperature produced yellower and greener fillets. A higher water temperature and a longer farming time produced softer cooked fillets, while the higher the water temperature was, the less juicy the cooked fillets were. A good correlation and complementarity were observed between sensory and instrumental analyses of the colour and texture of European catfish fillets. Copyright © 2007 Society of Chemical Industry
Cleaner production technologies for the palm oil industry
Authors: Puah Chiew Wei , Choo Yuen May , Ma Ah Ngan , Chuah Cheng Hock 
Published: February 2007

AbstractThis paper discusses some potential cleaner production technologies for the palm oil industry. These include supercritical fluid extraction, short path distillation and membrane separation. Over the last two decades, palm oil and minor components especially phytonutrients such as carotenoids, tocols (tocopherols and tocotrienols), sterols, squalene and phospholipids have received much attention for their nutritional properties. The recovery of these phytonutrients is a challenging task because (i) some of them (e. g. carotenoids and vitamin E) are sensitive to heat, light and air; (ii) they are of different polarity, from non‐polar (e. g. squalene) to relatively polar (e. g. phospholipids) and (iii) they are of differing molecular weights. Suitable technologies are needed to recover all these phytonutrients without damage. The paper discusses the latest development of these technologies.
Anisotropic curve shortening flow in higher codimension
Authors: Pozzi Paola 
Published: February 2007

AbstractWe consider the evolution of parametric curves by anisotropic mean curvature flow in ℝn for an arbitrary n⩾2. After the introduction of a spatial discretization, we prove convergence estimates for the proposed finite‐element model. Numerical tests and simulations based on a fully discrete semi‐implicit stable algorithm are presented. Copyright © 2007 John Wiley & Sons, Ltd.
Adaptive stabilization of Kirchhoff's non‐linear strings by boundary displacement feedback
Authors: Kobayashi Toshihiro , Sakamoto Tetsuzo 
Published: February 2007

AbstractThis paper is concerned with adaptive global stabilization of an undamped non‐linear string in the case where any velocity feedback is not available. The linearized system may have an infinite number of poles and zeros on the imaginary axis. In the case where any velocity feedback is not available, a parallel compensator is effective. The adaptive stabilizer is constructed for the augmented system which consists of the controlled system and a parallel compensator. It is proved that the string can be stabilized by adaptive boundary control. Copyright © 2007 John Wiley & Sons, Ltd.
How to make your article more acceptable for the statistical reviewer
Authors: Herbison Peter 
Published: February 2007

AbstractMany medical articles have problems with methodological aspects. To help prevent this, medical statisticians should be more involved in all aspects of medical research. Having more statistical reviewing of manuscripts submitted to journals should also help, but will not cure the problem. This paper makes some suggestions that may help authors make manuscripts more acceptable methodologically, but there is no substitute for statistical involvement throughout the research process. Neurourol. Urodynam. 26:318–322, 2007. © 2007 Wiley‐Liss, Inc.
A study on the performance of natural neighbour‐based Galerkin methods
Authors: Alfaro I. , Yvonnet J. , Chinesta F. , Cueto E. 
Published: February 2007

AbstractIn this paper we address the problem of improving natural element simulations in terms of computational cost. Several problems are discussed, that include an efficient natural neighbour search algorithm and a comparison of different natural neighbour‐based interpolation algorithms. In particular, we review the so‐called pseudo‐NEM, a moving least squares‐like approximation scheme that employs natural neighbours, and compare it with traditional Sibson and Laplace interpolation schemes in terms of both accuracy and computational cost. Some examples in linear Elasticity and visco‐plasticity are analysed in order to test the proposed schemes in engineering problems. Copyright © 2007 John Wiley & Sons, Ltd.
Foetal magnetic resonance imaging and echogenic bowel
Authors: Carcopino Xavier , Chaumoitre Kathia , Shojai Raha , Akkawi Reem , Panuel Michel , Boubli Léon , D'ercole Claude 
Published: February 2007

AbstractObjectivesTo evaluate how foetal magnetic resonance imaging (MRI) may change the diagnosis in cases of ultrasound (U/S) findings of echogenic bowel (EB).MethodsSeventeen foetuses with EB underwent serial U/S examinations, foetal MRI, cystic fibrosis screening and maternal viral serologic tests. MRI protocol included T2‐weighted half‐Fourier acquired single‐shot turbo spin‐echo (HASTE) sequence and gradient echo (GE) T1‐weighted images. Foetal abdominal MRI analyzed patterns were size and signal of small bowel, colon and rectum, ascites and abdominal mass. All neonates had complete clinical examination, abdominal sonography, and a 6 months clinical follow‐up.ResultsEleven foetuses with isolated EB had normal MRI and normal outcome. In comparison, all the 6 foetuses whose U/S patterns showed associated signs had abnormal MRI (p < 0.001). Five had proven pathology (83.3%: 5/6) and only 1 (16.7%: 1/6) had no proven pathology and normal postnatal outcome (p = 0.001). For those five, foetal MRI showed bowel abnormalities with one case of bowel duplication and four cases of bowel obstruction. Two out of the four cases of bowel obstruction were genetically diagnosed as cystic fibrosis. The two remaining cases were diagnosed as ileal atresia.ConclusionMRI could provide additive information in cases of EB associated with bowel dilatation. Copyright © 2007 John Wiley & Sons, Ltd.
Passivating thin bifacial silicon solar cells for industrial production
Authors: Janßen L. , Rinio M. , Borchert D. , Windgassen H. , Bätzner D. L. , Kurz H. 
Published: February 2007

AbstractA scheme for passivating thin multi‐crystalline silicon solar cells compatible to mass production is presented. Wafers with a thickness of 180 µm were processed into solar cells. The otherwise severe bowing has been avoided by reduced aluminium coverage on the rear surface. The process scheme includes a silicon nitride firing through step for conventional screen printed contacts, where a silicon nitride layer on the rear surface acts as surface passivation layer and enables a gain in efficiency of 0.6% [abs.]. Copyright © 2007 John Wiley & Sons, Ltd.
Correlation of the rates of solvolysis of diphenylphosphinyl chloride using an extended form of the Grunwald–Winstein equation
Authors: Kevill Dennis N. , Koh Han Joong 
Published: February 2007

AbstractThe specific rates of solvolysis of diphenylphosphinyl chloride (1) have been measured at 25.0 °C in 30 solvents. For six representative solvents, studies were made at several temperatures and activation parameters determined. These were used to calculate a value at 25.0 °C in 100% 2,2,2‐trifluoroethanol (TFE) from values at higher temperatures. The 31 solvents gave a reasonable extended Grunwald–Winstein plot, correlation coefficient (R) of 0.920, which improved to 0.956 when the four TFE–ethanol points were excluded. The sensitivities (l and m) were similar to those obtained for dimethyl phosphorochloridate and phosphorochloridothionate and for N,N,N′,N′‐ tetramethyldiamidophosphorochloridate. As with the three previously studied solvolyses, an SN2 pathway is proposed for the solvolyses of 1. Copyright © 2007 John Wiley & Sons, Ltd.
Molecular structure of alkali metal 4‐nitrobenzoates
Authors: Regulska E. , Samsonowicz M. , Świsłocka R. , Lewandowski W. 
Published: February 2007

AbstractThe influence of lithium, sodium, potassium, rubidium, and cesium on the electronic system of the 4‐nitrobenzoic acid molecule was studied. The vibrational (FT‐IR, FT‐Raman) and NMR (1H and 13C) spectra for 4‐nitrobenzoic acid salts of alkali metals were recorded. The assignment of vibrational spectra was done. Characteristic shifts of band wavenumbers and change in band intensities along the metal series were observed. Good correlation between the wavenumbers of the vibrational bands in the IR and Raman spectra for 4‐nitrobenzoates and ionic potential, electronegativity, atomic mass, and affinity of metals were found. The chemical shifts of protons and carbons (1H, 13C NMR) in the series of studied alkali metal 4‐nitrobenzoates were observed too.Optimized geometrical structures of studied compounds were calculated by HF, B3PW91, B3LYP methods using 6‐311++G** basis set. The theoretical IR, Raman, and NMR spectra were obtained. The theoretical vibrational spectra were interpreted by means of potential energy distributions (PEDs) using VEDA 3 program. The calculated parameters were compared to experimental characteristic of studied compounds. Copyright © 2007 John Wiley & Sons, Ltd.
High‐pressure effects on the Diels–Alder reaction in room temperature ionic liquids
Authors: Vidiš Ana , Laurenczy Gábor , Küsters Ernst , Sedelmeier Gottfried , Dyson Paul J. 
Published: February 2007

AbstractThe effect of pressure on the Diels–Alder reaction was examined in room temperature ionic liquids, followed by high‐pressure FT‐IR spectroscopy using pressures up to 150 MPa. Pressure enhances the kinetic sensitivity of the reaction. The kinetic effect of fluorophobic interactions was examined using ionic liquids with fluorous cations. Ionic liquids in combination with ZnI2 as a Lewis acid catalyst were also studied under high pressure. Copyright © 2007 John Wiley & Sons, Ltd.
Oxidation of substituted triazines by sulfate radical anion (SO) in aqueous medium: a laser flash photolysis and steady state radiolysis study
Authors: Manoj P. , Prasanthkumar K. P. , Manoj V. M. , Aravind Usha K. , Manojkumar T. K. , Aravindakumar C. T. 
Published: February 2007

AbstractLaser flash photolysis has been used to determine the bimolecular rate constants and the spectral nature of the intermediates obtained by the reaction of sulfate radical anion (SO) with 1,3,5‐triazine (T), 2,4,6‐trimethoxy‐1,3,5‐triazine (TMT), 2,4‐dioxohexahydro‐1,3,5‐triazine (DHT), and 6‐chloro N‐ethyl N'‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine (atrazine, AT). The rate constants determined were in the range 4.6 × 107–3 × 109 dm3 mol−1 s−1 at pH 6. The transient absorption spectra obtained from the reaction of SO with T, TMT, DHT and AT has an absorption maximum in the region 320–350 nm and was found to undergo second‐order decay. The intermediate species is assigned to N‐yl C(OH) radical of T (TOH•), carbon centered neutral radical of TMT, an OH‐adduct of AT and an N‐centered radical in the case of DHT. The interpretations on the experimental results obtained from TMT are supported by DFT calculation using Gaussian 03. Steady state radiolysis technique has also been used to investigate the degradation of AT induced by SO. The degradation profile indicated that about 99% of AT has been decomposed after an absorbed gamma‐radiation dose of 7.5 kGy. The degradation yield of AT (expressed as G(‐AT)) was found to be 0.26 µ mol J−1. The degradation reactions initiated by SO may thus be employed as a potential alternative for •OH‐induced degradation of triazines. Copyright © 2007 John Wiley & Sons, Ltd.
Theoretical studies of the structures and optical properties of the bifluorene and its derivatives
Authors: Wang Ji‐Fen , Feng Ji‐Kang 
Published: February 2007

AbstractThe ground and excited structures of the molecules are compared basis on the calculated by HF and CIS, respectively. The ionization potentials (IPs), electron affinities (EAs) and HOMO–LUMO gaps (ΔEHOMO–LUMO) of the oligomers are studied by the density functional theory (DFT) with B3LYP functional while the vertical excitation energies (Egs) and the maximal absorption wavelength λabs of oligomers of bifluorene and its derivatives DFE, DFA, DFBT, FDBO, and FSCHD are studied employing the time dependent density functional theory (TD‐DFT) and ZINDO. Compared with BF, the derivatives DFE, DFA, and DFBT are better conjugated, easier to give an electron or a hole, as well as get an electron or a hole. Their HOMO–LUMO gaps are narrower and they have lower vertical excitation energies. The absorption and emission spectra of them are red shifting. However, FDBO and FSCHD are in the other way round. It is important that FDBO and FSCHD are good blue emitters. Copyright © 2007 John Wiley & Sons, Ltd.
Bis(salicylaldiminate)copper(II)/methylaluminoxane catalysts for homo‐ and copolymerizations of ethylene and methyl methacrylate
Authors: Galletti Anna Maria Raspolli , Carlini Carlo , Giaiacopi Simone , Martinelli Marco , Sbrana Glauco 
Published: February 2007

AbstractBis(salicylaldiminate)copper(II) complexes, when activated with methylaluminoxane, catalyzed the homo‐ and copolymerizations of ethylene and methyl methacrylate (MMA). The activity in the MMA homopolymerization was influenced by the electronic and steric characteristics of the Cu(II) precursors as well as the cocatalyst concentration. The same systems revealed modest activity also in the homopolymerization of ethylene, giving a highly linear polyethylene, and in its copolymerization with MMA. These copolymers exhibited a very high content of polar groups (MMA units > 70 mol %) and were characterized by a high molecular weight and polydispersity. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1134–1142, 2007
Radical graft polymerization of vinyl monomers onto nanoparticles in ionic liquid initiated by azo groups introduced onto the surface
Authors: Ueda Jun , Yamaguchi Hiroshi , Yamauchi Takeshi , Tsubokawa Norio 
Published: February 2007

AbstractThe radical graft polymerization of vinyl monomers, such as styrene and methyl methacrylate, initiated by azo groups introduced onto silica nanoparticle and carbon black surfaces in room temperature ionic liquid (IL) were investigated. In this work, 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([C4mim][PF6]) was used as IL. The percentage of polystyrene and poly(methyl methacrylate) grafting onto silica nanoparticle and carbon black increased with increasing reaction time. The percentage of grafting in IL was much larger than that in 1,4‐dioxane. The molecular weight of polystyrene grafted onto the silica surface in IL was almost equal to that in 1,4‐dioxane. The result indicates that the amount of grafted polystyrene in IL is five times that in 1,4‐dioxane. This may be due to the fact that lifetime of the surface radical formed by the group of azo is prolonged because of high viscosity of IL. Therefore, the surface azo groups were effectively used as initiating sites for the graft polymerization. In addition, the reduction of waste solvent was achieved by use of IL as reaction solvent, because unreacted monomer could be removed under vacuum after the reaction and the reuse of IL was easily achieved. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1143–1149, 2007