Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

The surface science of titanium dioxide

Signaling Recognition Events with Fluorescent Sensors and Switches.

TiO2 photocatalysis and related surface phenomena

Ru(II) polypyridine complexes: photophysics, photochemistry, eletrochemistry, and chemiluminescence

Ring Expansion of a three- to a five-membered cyclic structure in conjunction with loss of a carbalkoxy radical from the molecular ions is postulated for a series of 2,3-dicarbal-koxy-spiro-cyclopropane-1,9′-fluorenes. Initial rupture of the strained spiro-cyclopropane system with destruction of the distinct molecular geometry is inferred from virtually identical spectral patterns of, cis- and trans-isomers, whereas reclosure of the ‘open’ intermediate to a cyclopentadiene ring can be deduced from the secondary decomposition of the resulting (M–COOR) fragments. These latter ions exhibit loss of the second carbalkoxy group together with a hydrogen atom of unusual positional origin (1′ or its equivalent 8′) to form a pair of neutral species, ROH and CO. Since the ejection of hydrogen from aromatic positions can be taken as evidence of rearomatisation in the course of substitution, this origin is liable to mark the site of the new ring junction and thus to reflect the size of the enlarged cyclic moiety.

Ringerweiterung in organischen Molekeln unter Elektronenbeschuss: Die massenspektrometrische Fragmentierung von 2,3‐dicarbalkoxy‐spiro‐cyclopropan‐1, 9′‐fluorenen

Vibrational quenching of triplet states

We show the potential of miniemulsion photo­polymerization for the continuous production of aqueous poly(acrylate) dispersions in a microreactor at room tem­perature. While the starting acrylate nanoemulsions are amenable to limit scattering, their polymerization within a microreactor provides additionally small microchannels and short diffusion path enabling an efficient mixing in order to alleviate the constraints associated with non­uniform through­ cure in turbid medium. Two key features prove that this process design is highly eco­efficient: i) two types of energy ­saving and compact UV sources (fluo ­rescent or light­emitting diode) were employed; ii) high conversions were achieved using the fluorescent lamp with short residence times (10 min), low irradiance (3 mW cm ­2 ) and without the need of solvent. The present study describes briefly the influence of various parameters – flow rate, photo­initiator type/concentration, droplet size, solid content, UV source – on the photopolymeriza­tion course (kinetics) and the properties of the nanolatex obtained (particle size and molecular weight).

https://www.degruyter.com/view/j/gps.2014.3.issue-5/gps-2014-0051/gps-2014-0051.pdf

Synthesis of acrylic latex via microflow miniemulsion photopolymerization using fluorescent and LED UV lamps

The advance of 157 nm as the next photolithographic wavelength has created a need to for transparent and radiation durable polymers for the use as pellicles. The most promising materials for the pellicles are fluorinated polymers, but the currently available fluorinated polymers undergo photodegradation and/or photodarkening upon exposure to 157 nm irradiation. To understand the mechanism of the photodegradation and photodarkening of fluorinated polymers, mechanistic studies on the photolysis of liquid model fluorocarbons such as, perfluoro butylethyl ether and perfluoro-2H-3-oxa-heptane, were performed employing UV, NMR, FTIR, GC, and GC/MS analysis. All hydrogen containing compounds showed decreased photostability compared to the fully perfluorinated compounds. Irradiation in the presence of atmospheric oxygen showed reduced photodarkening compared to deoxygenated samples. Irradiations were performed at 157 nm, 172 nm, 185 nm, and 254 nm and showed only minor wavelength dependence. Mechanisms for photodegradation of the fluorocarbons were proposed, where Rydberg excited states are involved.

/pdf/157-nm-pellicles-for-photolithography-mechanistic-4t57xrczh0.pdf

157-nm pellicles for photolithography: mechanistic investigation of the deep-UV photolysis of fluorocarbons

Photodynamic effects of rose bengal, a well-known singlet oxygen sensitizer, and of haematoporphyrin derivative, the most widely used sensitizer in photodynamic therapy of tumours, could be visualized using sea urchin eggs and embryos. This biological material is a valuable model for the analysis of mechanisms and/or sites of the photodynamic action occurring in any living tissue. Depending on the sensitizer used, singlet oxygen may be identified as the main mediator of the cytotoxic effects observed. Besides observations made on the living, in particular within the context of fertilization ability of the egg cell, gross damages of the cells are morphologically analysed by scanning electron microscopy. The results support the working hypothesis explaining the different susceptibility of healthy and tumour cells for photosensitization as a cell cycle phenomenon.

André M. Braun

Papers

Ringerweiterung in organischen Molekeln unter Elektronenbeschuss: Die massenspektrometrische Fragmentierung von 2,3‐dicarbalkoxy‐spiro‐cyclopropan‐1, 9′‐fluorenen

Vibrational quenching of triplet states

Synthesis of acrylic latex via microflow miniemulsion photopolymerization using fluorescent and LED UV lamps

157-nm pellicles for photolithography: mechanistic investigation of the deep-UV photolysis of fluorocarbons

Primary effects of singlet oxygen sensitizers on eggs and embryos of sea urchins.