Image and Identity. The experimental Housing of Schorlemerallee, Hans and Wassili Luckhardt, Alfons Anker, Berlin 1925-30

Proceedings of the 12th DOCOMOMO International Conference

A principios de los años 90 ciudad europea era un insulto. Entrevista a Hans Stimmann

Hans Stimmann (Lübeck, 1941) será recordado en la historia del urbanismo como el creador de la estructura y buena parte de la imagen del llamado ?Nuevo Berlín?, es decir, del Berlín central reconstruido posterior a la caída del Muro, en lo que constituye la intervención urbana más importante en Europa desde la Segunda Postguerra Mundial. Además, Stimmann se ha convertido en un símbolo para todos aquéllos teóricos y arquitectos que buscan corregir el paradójico urbanismo anti-urbano que nos ha legado el siglo XX, pero que no disponían hasta hace poco de un paradigma consistente. Guiado por el análisis de la estructura de la ciudad europea desarrollado por Aldo Rossi en su celebrado libro-manifiesto de 1966, que fue también la primera denuncia seria del ?funcionalismo vulgar?, Stimmann parece haber llevado a la práctica aquella ?arquitectura de la ciudad? que la segunda mitad del siglo XX sólo había visto aparecer de manera tímida y ocasional.

Haus des Rundfunks en Berlin, de Hans Poelzig, 1930

Poelzig affirmed that the technical ideal consisted of using the least amount of shapes and materials possible. He understood architecture as an art, as the expression of form; In contrast to the indifference of the most widely recognized values of modernism: technical innovation in construction along with the functionality of buildings. The Haus des Rundfunks is a powerful hermetic factory in the shape of a triangle and of uniform height. Mass, geometric rigidity and the absence of textures make up a building which relinquishes expressing the new media, with a perimeter ring consisting of offices and larger spaces that are more characteristic towards their inside. Geometry is used as a means to organize and limit the shapes of the buildings. The arrangement and division of different intercommunicating spaces are subjected to the crudeness of their geometric limits. Interior spaces ranging from the most static to the most dynamic are defined through the qualities of materials and geometries. This turns the spaces into geometric grids which decompose the wall, floor and ceiling planes into fragments, regardless of the constructive reality provided by a metallic frame structure. Its polyhedral lamps enclose artificial and emphasize the value of the grid. Poelzig limits himself to dealing with planes within a closed volume of uniform height, and maintains geometric rigidity compatible with a certain degree of figurativeness. This article tries to bring to life this exemplary building, marked by its passivity and hermetism.

Por que as objeções de Hans Kelsen ao jusnaturalismo não valem contra a teoria do Direito Natural de Tomás de Aquino? / Júlio Aguiar de Oliveira e Bárbara Alencar Ferreira Lessa. --

Inclui bibliografia.

O princípio de maioria na doutrina de Hans Kelsen

Inclui bibliografia

Controle concentrado de constitucionalidade : o guardião da constituição no embate entre Hans Kelsen e Carl Schmitt

Inclui notas explicativas, bibliográficas e bibliografia

Poder constituinte e a norma fundamental de hans kelsen / José Luiz Quadros de Magalhães. --

Inclui notas bibliograficas.

Photochemically induced nuclear spin polarization in reaction centers of photosystem II observed by 13C-solid-state NMR reveals a strongly asymmetric electronic structure of the P680.+ primary donor chlorophyll

We report 13C magic angle spinning NMR observation of photochemically induced dynamic nuclear spin polarization (photo- CIDNP) in the reaction center (RC) of photosystem II (PS2). The light-enhanced NMR signals of the natural abundance 13C provide information on the electronic structure of the primary electron donor P680 (chlorophyll a molecules absorbing around 680 nm) and on the pz spin density pattern in its oxidized form, P680⨥. Most centerband signals can be attributed to a single chlorophyll a (Chl a) cofactor that has little interaction with other pigments. The chemical shift anisotropy of the most intense signals is characteristic for aromatic carbon atoms. The data reveal a pronounced asymmetry of the electronic spin density distribution within the P680⨥. PS2 shows only a single broad and intense emissive signal, which is assigned to both the C-10 and C-15 methine carbon atoms. The spin density appears shifted toward ring III. This shift is remarkable, because, for monomeric Chl a radical cations in solution, the region of highest spin density is around ring II. It leads to a first hypothesis as to how the planet can provide itself with the chemical potential to split water and generate an oxygen atmosphere using the Chl a macroaromatic cycle. A local electrostatic field close to ring III can polarize the electronic charge and associated spin density and increase the redox potential of P680 by stabilizing the highest occupied molecular orbital, without a major change of color. This field could be produced, e.g., by protonation of the keto group of ring V. Finally, the radical cation electronic structure in PS2 is different from that in the bacterial RC, which shows at least four emissive centerbands, indicating a symmetric spin density distribution over the entire bacteriochlorophyll macrocycle.

Large Upper Devonian arthrodires from Iran / Hans-Peter Schultze --

v.23:no.5(1973)

Megapleuron zangerli : a new dipnoan from the Pennsylvanian, Illinois / Hans-Peter Schultze --.

v.33:no.21(1977)