49 research outputs found
Verbundprojekt INGER: Neue Ansätze zur Integration von Geschlecht in die Forschung zu umweltbezogener Gesundheit.
In der biomedizinischen Forschung und Praxis zu Umwelt und Gesundheit wird Geschlecht mit den vielfältigen biologischen und sozialen Dimensionen noch nicht angemessen berücksichtigt. Das Verbundprojekt INGER hat zum Ziel, innovative Methoden für eine geschlechtersensible quantitative Forschung zu umweltbezogener Gesundheit interdisziplinär zu entwickeln und zu erproben. Neue Fragebogenmodule werden getestet, um die Datenerhebung in populationsbasierten Studien zu umweltbezogener Gesundheit durch umfassende Erhebung von Sex/GenderDimensionen entsprechend gendertheoretischer Konzepte zu verbessern. Zur Quantifizierung der Bedeutung von Sex/Gender für Umweltexpositionen und umweltbezogene Gesundheit werden neue statistische Analysestrategien identifiziert und erprobt. INGER wird eine fundierte Wissensbasis schaffen als Grundlage für eine bessere Berücksichtigung von Sex/GenderAspekten im umweltbezogenen Gesundheitsschutz und in der Gesundheitsförderung im Bereich Umwelt und Gesundheit
Sequential Photosubstitution of Carbon Monoxide by (E)-Cyclooctene in Hexacarbonyltungsten: Structural Aspects, Multistep Photokinetics, and Quantum Yields
The photochemical conversion of W(CO)6 (1) into a trans-W(CO)4(η2-olefin)2 complex has been investigated using (E)-cyclooctene (eco) as a model olefin possessing extraordinary coordination properties. trans-W(CO)4(η2-eco)2 (4) is generated as an equimolar mixture of two diastereoisomers (4a, S symmetry; 4b, D2 symmetry) which can be separated by fractional crystallization. The entire reaction sequence involves the intermediate formation of W(CO)(η2-eco) (2) and cis-W(CO)(η2-eco)2 (3: two diastereoisomers, 3a and 3b, with apparent C and C symmetry, respectively). Complexes 2 and 3, although difficult to isolate from the photochemical reaction mixture, are conveniently accessible via alternative thermal ligand exchange routes. The molecular structures of 2 and 4a in the crystal were determined by X-ray diffraction techniques. The olefin double bonds, with trans-orthogonal arrangement in 4a, are eclipsed to a OC−W−CO axis in either case. The course of the conversion of 1 into the olefin-substituted products was monitored by quantitative IR spectroscopy. Photokinetic equations developed for this study describe the concentrations of all four components as implicit functions of the amount of light absorbed by the system, of the quantum yields of the individual photoprocesses, and of the UV−vis absorbance coefficients of the compounds involved. Based on these functional relationships, the individual quantum yields at λexc = 365 nm (Φ12 = 0.73, Φ23 = 0.34, Φ24 = 0.16, Φ34 = 0.15) were evaluated from a series of experimental data sets by an iterative procedure which involves variation of the quantum yield input data until the best fit of the computed to the measured concentrations is achieved. Low-temperature matrix isolation techniques were employed to characterize the W(CO)(η2-eco) fragment (5) as a key intermediate in the photolysis of W(CO)5(η2-eco) (2)
Gold nanoparticle patterning of silicon wafers using chemical e-beam lithography
This paper demonstrates a novel facile method for fabrication of patterned arrays of gold nanoparticles on Si/SiO2 by combining electron beam lithography and self-assembly techniques. Our strategy is to use direct-write electron beam patterning to convert nitro functionality in self-assembled monolayers of 3-(4-nitrophenoxy)-propyltrimethoxysilane to amino functionality, forming chemically well-defined surface architectures on the 100 nm scale. These nanopatterns are employed to guide the assembly of citrate-passivated gold nanoparticles according to their different affinities for amino and nitro groups. This kind of nanoparticle assembly offers an attractive new option for nanoparticle patterning a silicon surface, as relevant, for example, to biosensors, electronics, and optical devices