Search results for "Eating"
showing 10 items of 1247 documents
Calixarenes as Stoppers in Rotaxanes
1998
The synthesis of the amide-based rotaxane 7a bearing calix[4]arene blocking groups is described for the first time. While rotaxane formation fails if a calix[4]arene is functionalized at the upper rim with only an amino or methylamino group lacking any spacer, the prolonged amine 5a works successfully as stopper unit preventing dethreading of the dimeric wheel 1a by its size. Rotaxane formation of 8b was observed only by MALDI-TOF mass spectrometry of the reaction mixture of the amine 5b, the axle 6 and 1a. With the larger trimeric wheel 1b no stable rotaxane could be obtained. It either does not act as a concave template or its opening is too wide, even for the bulky calixarene stoppers.
Über die wirksamkeit von lewis-basen als initiatoren der anionischen polymerisation von formaldehyd. 27. Mitt. über polyoxymethylene
1966
Die anionische Polymerisation des monomeren Formaldehydes mit LEWIS-Basen wurde bei −78°C in Ather, Aceton und Toluol untersucht. Die Basizitat der LEWIS-Basen ist ein wichtiger Faktor for ihre Initiatoraktivitat, ist jedoch nicht allein entscheidend; es spielen auch strukturelle und steren rische Faktoren eine Rolle. Primare Amine sind wahrscheinlich deshalb schlechte Initiatoren, weil sie mit Formaldehyd Methylol- und Dimethylolamine bilden. Verzweigungen aliphatischer Substituenten wirken sich um so starker retardierend aus, je naher sich die Verzweigungsstelle am Stickstoffatom befindet. Die Polymerisationsgeschwindigkeit steigt bei den meisten Aminen mit zunehmender Polaritat des Losun…
ChemInform Abstract: Heterocycles from α-Aminonitriles
2014
Owing to their various modes of reactivity, α-aminonitriles represent versatile building blocks for the construction of a wide range of nitrogen heterocycles. The present Concept article focuses on synthetic methodologies using their bifunctional nature which is the basis of their reactivity as α-amino carbanions and as iminium ions. Reactions exclusively taking place on either the amine or on the nitrile moiety will not be considered.
ChemInform Abstract: Reversal of Asymmetric Induction in Stereoselective Strecker Synthesis on Galactosyl Amine as the Chiral Matrix.
1989
Abstract The reversal of the direction of asymmetric induction in Lewis acid catalyzed Strecker synthesis using the 2,3,4,6-tetra-O-pivaloyl-β-D-galactopyranosyl amine 1 is described. In isopropanol or tetrahydrofuran 1 had given ( R )-diastereomers of the corresponding α-amino nitriles preferably. However, in chloroform in the presence of heterogeneous zinc chloride the same auxiliary alternatively leads to an excess of the ( S )-diastereomers.
Ethyl 1-acetyl-3-amino-1H-pyrazole-4-carboxylate, a tetragonal structure with Z′ = 4
2006
The title compound, C8H11N3O3, crystallizes with Z' = 4. One pyrazole N atom is substituted and excluded from intermolecular contacts. The amine N, acetyl O and an ester O atom are involved in the formation of nearly planar molecular layers. The layers are perpendicular to the c axis, with an interlayer distance of 3.333 Å. The hydrogen-bonding patterns are similar for each molecule, i.e. intramolecular N-H...O, as well as intermolecular N-H...O and C-H...N(pyrazole), bonds are present.
Les préférences alimentaires
2018
National audience
Power of Cognition: How Dysfunctional Cognitions and Schemas Influence Eating Behavior in Daily Life Among Individuals With Eating Disorders
2018
Eating disorders (EDs) are characterized by marked cognitive distortions and maladaptive schemas. Cognitive models of EDs highlight the direct impact of cognitive dysfunctions on eating-related disturbances, insofar as specific cognitive contents such as thoughts about diet rules and food or loss of control may trigger disturbed eating behavior. Moreover, early maladaptive schemas that reflect perfectionist standards and relate to achievement and performance seem to be associated with disturbed eating, e.g., via their impact on situation-specific appraisals. However, so far, no study has investigated these assumptions. Hence, the present study sought to demonstrate whether and how cognitive…
The Binge Eating Scale: Structural Equation Competitive Models, Invariance Measurement Between Sexes, and Relationships With Food Addiction, Impulsiv…
2019
Introduction: The Binge Eating Scale (BES) is a widely used self-report questionnaire to identify compulsive eaters. However, research on the dimensions and psychometric properties of the BES is limited. Objective: The aim of this study was to examine the properties of the Spanish version of the BES. Methods: Confirmatory Factor Analyses (CFAs) were carried out to verify the BES factor structure in a sample of Spanish college students (N = 428, 75.7% women; age range = 18–30). An invariance measurement routine was carried out across sexes, the latent means were compared, and estimates of reliability and convergent and discriminant validity were presented. Results: A one-factor model fit the…
Heating and cooling with a heat pump
2009
Sub-Structuring Dynamics and Heating in Dense Coronal Structures
2005
Dense coronal plasma is confined in magnetic loops, the building blocks of the bright X-ray corona. We overview recent findings from the analysis of confined coronal plasma observed with SoHO and TRACE and its interpretation. Internal substructuring, mass transport and dynamics, and heating processes are discussed.