IDENTIFICATION OF NITROGEN COMPOUNDS AND THEIR EVOLUTIONDURINGAGEING NABSENCE ANDPRESENCE OF ADDITIVES EFFICIENCYOFHYDROTREATMENT

As established by several previous works, nitrogen compounds play a prominent role in the evolution of middle distillates containing cracked components, particularly regarding sediment formation and color evolution.

In a first part, this paper describes and compares stability properties of fuel blends using both an accelerated ageing method at 120°C (248°F ) and long term storage methods at 43°C(110°F) -ASTM 0 4625 - and at ambient temperature. Effectiveness of stabilizing additives is also evaluated. In mixtures containing LCOs, insoluble products are formed progressively during ageings, more or less rapidly according to the chemical constitution of the mixtures.

Then, it reports the complete identification of nitrogen compounds using gas chromatography equipped with a selective nitrogen detector and mass spectrometry showing that in light cycle oils, alkyl indoles and carbazoles are the main families.

Evolution of these compounds was followed kinetically during ageings in absence and presence of additives and alkyl indoles appeared as the moat evolutionary.

It appeared that some additives avoided evolutions of alkyl indoles without preventing sediment formation and color evolution. Oxidation mechanism involving nitrogen compounds should not be the only one to explain the storage evolutions of middle distillates.

Hydrotreatment converts all the alkyl indoles of LCO and prevents coloration end deposits in the storage of the mixtures of steaight-run distillates and LCOs.     

Formation of pearlitic banded structures in ferritic-pearlitic steels

The conditions for ferrite and pearlite banding in strip and plate made of structural steels were investigated. Factors found to influence the formation of banded structures were the cooling rate during the γ/α-transformation, the former austenite grain size, and the work-hardened condition of the former austenite. Analyses with the aid of an electron beam microprobe made it possible to demonstrate that the carbon-rich bands correspond locally with banded manganese enrichments, yet that they do not form before the course of the γ/α-transformation as a result of secondary segregation. It was possible to explain the mechanism of action of the influencing factors on the basis of this model.     

The Berlekamp-Massey Algorithm revisited

We propose a slight modification of the Berlekamp-Massey Algorithm for obtaining the minimal polynomial of a given linearly recurrent sequence. Such a modification enables to explain it in a simpler way and to adapt it to lazy evaluation. partially supported by the Galois Theory and Explicit Methods in Arithmetic Project HPRN-CT-2000-00114 partially supported by the European Union funded project RAAG CT-2001-00271     

On the Locus of Speed-Accuracy Trade-Off in Reaction Time: Inferences From the Lateralized Readiness Potential.

Lateralized readiness potentials (LRPs) were used to determine the stage(s) of reaction time (RT) responsible for speed-accuracy trade-offs (SATs). Speeded decisions based on several types of information were examined in 3 experiments, involving, respectively, a line discrimination task, lexical decisions, and an Erikson flanker task. Three levels of SAT were obtained in each experiment by adjusting response deadlines with an adaptive tracking algorithm. Speed stress affected the duration of RT stages both before and after the start of the LRP in all experiments. The latter effect cannot be explained by guessing strategies, by variations in response force, or as an indirect consequence of the pre-LRP effect. Contrary to most models, it suggests that SAT can occur at a late postdecisional stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Polymeric materials

Summary The Polymer Section of the Santa Barbara Workshop on Modeling of Materials is briefly reviewed. Motivation and need for modeling in polymer-based materials are outlined and the recommendations resulting from the workshop reported.     

Molecular basis and species specificity of high affinity binding of vasoactive intestinal polypeptide by the rat secretin receptor

The affinity and specificity of the binding interaction between ligands and their receptors are key for appropriate hormonal regulation of target tissues. However, it is now apparent that vasoactive intestinal polypeptide (VIP) binds to the rat secretin receptor with similar affinity to that for its natural ligand, secretin (Holtmann et al., 1995). In this report, we establish that this is not a characteristic of the human secretin receptor, and use rat-human secretin receptor chimeras, site mutants and truncated receptor constructs to establish the molecular basis for this unusual binding interaction. Of note, isolated N-terminal domains of the rat secretin and the VIP receptors are capable of high affinity binding of VIP. In the recently recognized secretin family of receptors, this domain has six conserved cysteine residues and disulfide bonds that are likely important to achieve the complex conformation critical for this binding. A single acidic residue (Asp98) present in the rat secretin receptor appears to be critical, because a site-mutant changing this to the polar, but uncharged residue present in that position in the human receptor (Asn) eliminates the high affinity binding of VIP. Of interest, a previously identified critical basic residue in VIP (Lys15) provides a candidate for charge-pairing with this residue, potentially aligning the peptide ligand in a nonproductive orientation within this receptor.     

A two-layer fuzzy pattern matching procedure for the evaluation of conditions involving vague quantifiers

In this note, we are interested in the evaluation of conditions of the form The value of attribute a for Q items of X is in F or more shortly Q items of X are F, where X is a set of items, Q denotes a possibly vague proportion (which may be linguistically expressed, e.g. most), F is a (possibly fuzzy) subset of the attribute domain of a. and where the available knowledge about the value a(x) of the attribute a for any item x may be imprecise or even vague. The evaluation is based on a fuzzy pattern matching procedure repeated two times. Such conditions may be encountered in queries addressed to an incomplete information data base or in the if-part of expert rules.     

Verminderung des Gehaltes von Blei und anderen Elementen in Wein mit Hilfe von Pectins?ure

Zusammenfassung Der Bleigehalt von Wein kann durch Zusatz von Pectinsäure (PS) vermindert werden. Die Wirksamkeit der Bleiverminderung durch PS hängt von der Qualitätsstufe des Weines ab. In Auslesewein (Wein A) senkten 6250 mg PS/1 den Bleigehalt in 24 h von 0,88 mg/l auf 0,28 mg/l und in Spätlese (Wein B) von 0,83 mg/l auf 0,06 mg/1. Unter den gleichen Bedingungen nahm in Wein A der Gehalt an Fe, Zn und Cu von 8,85 mg/l auf 7,05 mg/1, von 4,75 mg/l auf 1,25 mg/l and von 0,67 mg/l auf 0.57 mg/l ab; bei Wein B reduzierte sich der Gehalt von Fe, Zn und Cu von 6,70 mg/l auf 5,41 mg/1, von 1,17 mg/l auf 0,28 mg/l und von 0,46 mg/l auf 0,28 mg/1. Durch Filtration des Weines wurde PS nahezu quantitativ entfernt. Eine geschmackliche Beeinträchtigung des Weines durch PS ist bei 750 mg and 1500 mg PS/1 nicht feststellbar, jedoch bei 6 250 mg PS/1 nicht auszuschließen. Aufgrund ihrer hohen Bindungsaffinität zu Blei scheint PS geeignet, Blei auch aus anderen flüssi-gen Lebensmitteln zu entfernen.

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Reduction of lead content and of other metals in wine by means of pectic acid

Summary A procedure for reducing the Pb content in wines containing high levels of Pb is described. The reduction of Pb by means of pectic acid (PA) depends on the quality grade of the wine. In Auslese (wine A) 6250 mg PA/l diminished Pb content in 24 h from 0.88 mg/l to 0.28 mg/1; in Spatlese (wine B) from 0.83 mg/l to 0.06 mg/1. Under the same conditions the content of Fe, Zn, Cu decreased in wine A from 8.85 mg/l to 7.05 mg/1, from 4.75 mg/l to 1.25 mg/1, from 0.67 mg/l to 0.57 mg/l and in wine B from 6.70 mg/l to 5.41 mg/1, from 1.17 mg/l to 0.28 mg, 0.46 mg/l to 0.28 mg/l, respectively. PA is removed almost quantitatively by filtration. Sensory properties of treated wines were unchanged with concentrations of PA of 750 mg and 1500 mg/l. A slight effect on taste at 6250 mg PA/l wine cannot be excluded. On account of its high affinity to Pb, PA will probably remove Pb from other liquid foods as well.