Search results for "Zen"
showing 10 items of 3479 documents
ChemInform Abstract: Two Strained Hexahelicenophanes.
2000
The crystal structures of the [6]helicenes 4,13-(1,10-decamethylenedioxy)hexahelicene, C36H34O2, (I), and 4,13-(1,8-octamethylenedioxy)hexahelicene, C34H30O2, (II), show strong steric interactions between the terminal benzene rings and the polymethylenedioxy chains. The shortest ring A and F distances amount to 2.941 (3) and 2.902 (3) A, respectively. The increased steric energy of the ground state is responsible for a significantly lower racemization barrier of (I) and (II) in comparison to the unsubstituted [6]helicene.
Tropylium cation capsule of hydrogen-bonded tetraurea calix[4]arene dimers
2001
The interaction between tropylium salts and tetraurea calix[4]arene derivatives (such as 1 and 2) was studied in solution using 1D, 2D, diffusion, VT NMR and UV–visible spectroscopy. It was found that tropylium salts form charge transfer complexes with both the monomers and dimers of the tetraurea calix[4]arene derivatives depending on the experimental conditions. Compound 1 increases dramatically the solubility of tropylium salts in apolar solvents such as C2D4Cl2, CDCl3 and CD2Cl2 by forming the molecular capsule 1·C7H7+·1. In contrast to the benzene capsule of 1, in 1·C7H7+·1 the hydrogen bonds in the equatorial region that hold together the two parts of the dimer change their directiona…
Substituent effects in trans-p,p'-disubstituted azobenzenes: X-ray structures at 100 K and DFT-calculated structures.
2014
The crystal and molecular structures of twopara-substituted azobenzenes with π-electron-donating –NEt2and π-electron-withdrawing –COOEt groups are reported, along with the effects of the substituents on the aromaticity of the benzene ring. The deformation of the aromatic ring around the –NEt2group inN,N,N′,N′-tetraethyl-4,4′-(diazenediyl)dianiline, C20H28N4, (I), may be caused by steric hindrance and the π-electron-donating effects of the amine group. In this structure, one of the amine N atoms demonstrates clearsp2-hybridization and the other is slightly shifted from the plane of the surrounding atoms. The molecule of the second azobenzene, diethyl 4,4′-(diazenediyl)dibenzoate, C18H18N2O4,…
Halogen...halogen interactions in pressure-frozen ortho- and meta-dichlorobenzene isomers.
2007
Isomers 1,2-dichlorobenzene (o-DCB) and 1,3-dichlorobenzene (m-DCB) were high-pressure frozen in-situ in a Merrill–Bassett diamond–anvil cell and their structures determined at room temperature and at 0.18 (5) GPa for o-DCB, and 0.17 (5) GPa for m-DCB by single-crystal X-ray diffraction. The patterns of halogen...halogen intermolecular interactions in these structures can be considered to be the main cohesive forces responsible for the molecular arrangements in these crystals. The molecular packing of dichlorobenzene isomers, including three polymorphs of 1,4-dichlorobenzene (p-DCB), have been compared and relations between their molecular symmetry, packing arrangements, intermolecular inte…
From Zeno to Chrysippus
2015
This chapter is about the origin and development of early Stoic epistemology. I discuss how Zeno of Citium, the founder of the Stoa, was influenced by his predecessors and interpreted by his successors. I argue that Stoicism rely on two basic assumptions for which Socrates is the main predecessor, namely that human beings are at home in the world and that it is only by using our rational abilities to detect salient truths and organize them into skills that we can successfully orient ourselves in this world. This Socratic-Stoic position relies on a naturalistic theory of concept acquisition, for which Aristotle is the main predecessor, or so I argue. I then look at how Zeno’s original episte…
Current challenges and prospective analysis of the Third Sector of Social Action (TSSA) in Spain
2020
This paper analyses the current conditions and future challenges faced by the Third Sector of Social Action (TSSA) in Spain to consolidate itself as an institutional sphere of sustainable welfare and as a strategic actor in the development of social policies. The empirical basis of this work has been obtained with the use of qualitative methods such as in-depth interviews, focus groups and the mixed method of Delphi. The use of these methods is aimed at interpreting TSSA leaders' discourses, the collective voice of Non-governmental organisations (NGO) managers and representatives, and the opinions of experts on: the nature and past development of the sector. This research was carried out un…
A systematic narrative review of prosociality in educational leadership
2018
Organizational scholars have vigorously and long studied being prosocial in defining ‘prosociality’ as motivation, behavior, and impact to help or benefit others. This study attempts to provide an overview of previous studies that have approached the elements of being prosocial in educational leadership contexts. However, most of the prosocial elements in education are not explicitly defined as prosociality and have not yet been systematically studied. Thus, this study explored the research questions: (a) What elements could be involved in prosociality within educational leadership? (b) Who could be involved in the process of prosociality in educational leadership? The final corpus of this …
Adolfo Bioy Casares: la ficción biopolítica
2017
ABSTRACTMost academic works on Adolfo Bioy Casares can be put into two categories: those that stress Bioy Casares's political ideas and those that emphasize his mastery of the fantastic genre as if he were two different writers at once. Can we read a politics of the fantastic in his works? Beyond the Peronist polemics in which Casares's books are framed, if we take into consideration the existential logic that runs through his novels—always in the boundaries between life and death, dream and reality, body and spirit, etc.—we note an exploration of the body and living, of the human and the animal. This exploration is informed by scientific laws that progressively invade the spheres of subjec…
Acid- and Base-Catalysis in the Mononuclear Rearrangement of Some (Z)-arylhydrazones of 5-Amino-3-benzoyl-1,2,4-oxadiazole in Toluene: Effect of Subs…
2011
The reaction rates for the rearrangement of eleven (Z)-arylhydrazones of 5-amino-3-benzoyl-1,2,4-oxadiazole 3a-k into the relevant (2-aryl-5-phenyl-2H-1, 2,3-triazol-4-yl)ureas 4a-k in the presence of trichloroacetic acid or of piperidine have been determined in toluene at 313.1 K. The results have been related to the effect of the aryl substituent by using Hammett and/or Ingold-Yukawa-Tsuno correlations and have been compared with those previously collected in a protic polar solvent (dioxane/water) as well as with those on the analogous rearrangement of the corresponding (Z)-arylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole 1a-k in benzene. Some light can thus be shed on the general di…
Lipid-Altering Efficacy of Ezetimibe/Simvastatin 10/20 mg Compared to Rosuvastatin 10 mg in High-Risk Patients with and without Type 2 Diabetes Melli…
2010
AIMS: This post hoc analysis compared the effects of switching to ezetimibe/simvastatin 10/20 mg (EZE/SIMVA) or rosuvastatin 10 mg (ROSUVA) in uncontrolled high-risk hypercholesterolemic patients with/without type 2 diabetes mellitus (T2DM) despite statin monotherapy. METHODS: Patients (n = 618) at high risk for coronary vascular disease with elevated LDL-C ≥100 and ≤190 mg/dL despite use of statins were randomized 1:1 to double-blind EZE/SIMVA 10/20 mg or ROSUVA 10 mg for 6 weeks. Patients were classified as having T2DM based on ≥1 of the following: diagnosis of T2DM, antidiabetic medication, or FPG ≥126 mg/dL. This analysis evaluated percent changes from baseline in lipids among patients …