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The adsorption behavior of thin films of 4-alkoxybenzoic acids (with either hydroxy-, methoxy-, propoxy-, pentoxy- and decoxy-chains) and terephthalic acid, evaporated on a Highly Oriented Pyrolytic Graphite (HOPG) surface was studied. The orientation of the molecules was characterized by Metastable Induced Electron Spectroscopy (MIES) and Ultraviolet Photoelectron Spectroscopy (UPS(HeI)). On HOPG the 4-alkoxybenzoic acids and the terephthalic acid show a layer like growth at the beginning. Since the MIE spectra for the molecules on HOPG show all molecular orbitals, especially the π orbitals of the phenyl ring, a flat laying orientation on the graphite surface is assumed. The only exception is observed for 4-decoxy-benzoic acid. After a coverage of approximately 1 monolayer (ML) the spectrum is dominated by the spectral features of the alkyl structures.

The natural product punicine (Punica granatum) exists in two tautomeric forms, the cross-conjugated mesomeric betaine 1-(pyridinium-1-yl)-2-hydroxy-phenyl-5-olate and the conjugated mesomeric betaine 1-(pyridinium-1-yl)-5-hydroxy-phenyl-2-olate. Punicine as well as its picoline derivatives reacted with tris(pentafluorophenyl)borane exclusively at the 2'-olate group to form zwitterionic borates. Correspondingly, the 5'-dehydroxy derivate of punicine, the conjugated heterocyclic mesomeric betaine 1-(pyridinium-1-yl)-phenyl-2-olate and its picoline derivatives also gave borates, whereas analogous reactions of the cross-conjugated isomer 2'-dehydroxypunicine [1-(pyridinium-1-yl)-phenyl-3-olatel did not result in the formation of stable adducts. (C) 2020 Elsevier Ltd. All rights reserved.

The adsorption behavior of thin films of terephthalic acid (TPA) evaporated on a gold surface as well as on an aluminum foil was studied. The orientation of the molecules was characterized by metastable induced electron spectroscopy (MIES) and ultraviolet photoelectron spectroscopy (UPS). To make sure that the evaporation of TPA is nondestructive, additional X-ray photoelectron spectroscopy (XPS) was performed. These measurements also exclude any radiation damage. TPA on the gold surface shows a well-ordered layer growth up to 7.5 nm. Since the MIES spectra show both the acid structure and the phenyl group, a flat-laying orientation is assumed. In contrast, the phenylic carbon structure could not be observed while evaporating TPA on the oxidized aluminum foil. The MIES/UPS spectra only show the COOH group. To exclude a random arrangement of the molecules we also performed low temperature measurements. It can be concluded from these measurements, in addition to the fact that the work function increases during the evaporation, that TPA has a perpendicular arrangement on the aluminum foil.

This review tries to shed light on the early history of different methods for the generation of N-heterocyclic carbenes (NHCs), i.e., the extrusion of heterocumulenes (decarboxylations) from suitable mesomeric betaines, deprotonations of hetarenium salts, α-eliminations, tautomerizations of mesomeric betaines, and reductive desulfurizations of cyclic thioureas. Selected examples of acyclic and three- to eight-membered NHCs are presented, as well the generation of selected five- and six-membered anionic NHCs.

(1980). Juan Pablo Bonta, Architecture and Its Interpretation: A Study of Expressive Systems in Architecture. Art Journal: Vol. 40, Modernism, Revisionism, Plurism, and Post-Modernism, pp. 423-427.

(1980). Roger Scruton, The Aesthetics of Architecture. Art Journal: Vol. 40, Modernism, Revisionism, Plurism, and Post-Modernism, pp. 423-427.

S OF PAPERS PRESENTED AT THE TWENTY-FOURTH ANNUAL MEETING OF THE SOCIETY OF ARCHITECTURAL HISTORIANS Chicago, Illinois, January 28-31, 1971

emerges for extreme caution when linking words and deeds, statements and meanings; there can be an enormous gap between them. This reminds me of the statement by Mme. Syrkus which was quoted today by Mrs. Moholy-Nagy in such a manner that we could understand it as an admirable, profound plea for a deepening and enriching of the architectural vocabulary. But when it was made, it came forth in defense of the then party line of Social Realism in architecture and of schemes which were reactionary in many ways and embarrassing to look at because it was known from past record that those who presented them really could do better. Thus we have another example, as with the reaction in the 193os, of how tenuous the connection can be between what is said and what is designed, and how extremely cautious historians have to be when handling topics and material of this kind, especially when both "personal time" and "historic time" are involved.

During the first decades of the twentieth century, the Bund fur Heimatschutz espoused a reformed architecture responsible in equal measure to the environment, the modern world, and the continuity of tradition. A large and influential organization, its architectural discourse addressed diverse and seemingly irreconcilable issues: preservation of the natural and built domains and commitment to industrialization, advocacy of new materials and technologies and maintenance of tradition, belief in contemporary life and support of indigenous culture.