Quantitative three-dimensional imaging of soot volume fraction in turbulent non-premixed flames

A three-dimensional (3-D) imaging system for studies of reactive and non-reactive flows is described. It can be used to reveal the topology of turbulent structures and to extract 3-D quantities, such as concentration gradients. Measurements are performed using a high repetition rate laser and detector system in combination with a scanning mirror. In this study, the system is used for laser-induced incandescence measurements to obtain quantitative 3-D soot volume fraction distributions in both laminar and turbulent non-premixed flames. From the acquired data, iso-concentration surfaces are visualised and concentration gradients calculated.     

Advantages of Monodisperse and Chemically Robust “SpheriCal” Polyester Dendrimers as a “Universal” MS Calibrant

The utilization of dendrimer calibrants as an alternative to peptides and proteins for high mass calibration is explored. These synthetic macromolecules exhibited a number of attractive advantages, including exceptional shelf-lives, broad compatibility with a wide range of matrices and solvents, and evenly spaced calibration masses across the mass range examined, 700–30,000 u. The exceptional purity of these dendrimers and the technical simplicity of this calibration platform validate their broad relevance for high molecular weight mass spectrometry.

Shape coexistence in the neutron deficient Pb isotopes and the configuration-constrained shell correction approach

Calculations of shape-isomeric states in neutron deficient lead isotopes have been performed using the configuration-constrained shell correction method with a Woods-Saxon average potential and a monopole pairing interaction. This approach enables us to decompose the ground state potential energy surface in separate parts characterized uniquely by the number of occupied intruder orbitals. The calculations reproduce the positions of the excited 0⁺ intruder states. The isotope¹⁹⁶Pb is discussed in detail.     

Hyperfine structure measurements of103Rh

Hyperfine structure has been measured in 28 states of¹⁰³Rh below 34,000 cm^?1. The magnetic dipole interactionA constants in the metastable states 4d ⁸ 5s ⁴ P _5/2,3/2,² P _3/2,1/2,² D _5/2,3/2,² G _9/2,7/2 and 4d ⁷ 5s ^{2 4} F _{9/2,7/2,5/2,3/2} have been determined using the laser radio-frequency double-resonance method and in the states 4d ⁸ 5p ⁴ D _{7/2,5/2,3/2,1/2},⁴ G _7/2,5/2,⁴ F _{9/2,7/2,5/2,3/2},² G _9/2,7/2,² F _7/2,5/2 and² D _5/2,3/2 by high-resolution laser spectroscopy.     

Construction of isarithms and isarithmic maps by computers

The most important consideration in map construction is that the finished map shall give an objective picture of the actuality it represents. It is also important that the map can be produced quickly and efficiently with a minimum of manual labor. The coordinate mapping method fulfils these requirements to a very high degree. This article deals with isarithmic mapping methods adapted to the coordinate mapping method and to computers and automatic data processing.     

Cubic interaction terms for arbitrarily extended supermultiplets

Using a light-cone superspace formalism we construct cubic interaction terms for all maximally extended supersymmetry multiplets where the maximum helicity λ is an integer. The coupling constants have dimension [length]^λ?1 and there is a gauge group for any odd λ.     

A selective intramolecular 5-exo-dig or 6-endo-dig cyclization en route to 2-furanone or 2-pyrone containing tricyclic scaffolds

Ringfused bicyclic 2-pyridones exhibit interesting biological properties against pili assembly in uropathogenic Escherichia coli (Pinkner, J. S. et al. Proc. Natl. Acad. Sci. U. S. A.2006, 103, 17897-17902; ?berg, V. et al. Org. Biomol. Chem.2007, 5, 1827-1834) as well as curli formation (Cegelski, L. et al. Nat. Chem. Biol.2009, 5, 913-919). In the search for new ring-fused central fragments, highly selective synthetic routes to the 2-furanone or 2-pyrone containing tricyclic scaffolds 1 and 2 have been developed.     

Identification of the sex pheromone of the lesser date moth, Batrachedra amydraula, using sequential SPME auto-sampling

The identification of the sex pheromone of the lesser date moth, Batrachedra amydraula (Meyrick) was based on GC-MS analysis of volatiles released by virgin females using sequential SPME auto-sampling of headspace and by synthesis of the key component, (4Z,7Z)-4,7-decadien-1-yl acetate. Substantial capture of males in a date palm plantation using a bait consisting of the key component and 5Z-decen-1-yl acetate in a ratio of 1:2 indicated that these are the essential components of the sex pheromone. Addition of 4Z-decen-1-yl acetate and decan-1-yl acetate, which were also identified, did not affect trap-capture. The lesser date moth is the first member of the Batrachedridae whose sex pheromone has been identified. (4Z,7Z)-4,7-Decadien-1-yl acetate is a novel compound among moth sex pheromones.     

Visualization of β‐carotene and starch granules in plant cells using CARS and SHG microscopy

Information on the content and bioavailability of provitamin A carotenoids, such as β‐carotene, in plant foods is of great interest due to the widespread vitamin A deficiency in developing countries. While the amount of β‐carotene can readily be quantified with analytical techniques, there is limited information on β‐carotene morphology in native plant materials. Here, we introduce nonlinear microscopy for three‐dimensional, label‐free imaging of carotenoids in fresh and thermally treated plant tissues, providing quantitative information at single‐aggregate level and detailed insight into their distribution. Carotenoids in orange‐fleshed sweet potato (OFSP), carrot, and mango were visualized by coherent anti‐Stokes Raman scattering (CARS) microscopy and, in the case of OFSP, related to the plant‐matrix morphology by simultaneous second‐harmonic generation (SHG) microscopy of starch granules. Sizes, shapes, densities, and location of different types of carotenoid bodies were quantified. While OFSP and carrot showed heterogeneous rod‐shaped bodies with high carotenoid densities indicated by higher CARS signals, the carotenoid‐filled lipid droplets in mango appeared as homogeneous low‐density aggregates of rounded shape. In addition, β‐carotene densities and morphologies in OFSP were studied after thermal processing, showing that the bodies remain intact despite significant changes of the surrounding starch granules. Copyright © 2010 John Wiley & Sons, Ltd.     

Laser-induced fluorescence of formaldehyde in combustion using third harmonic Nd:YAG laser excitation

Formaldehyde (CH2O) is an important intermediate species in combustion processes and it can through laser-induced fluorescence measurements be used for instantaneous flame front detection. The present study has focussed on the use of the third harmonic of a Nd:YAG laser at 355 nm as excitation wavelength for formaldehyde, and different dimethyl ether (C2H6O) flames were used as sources of formaldehyde in the experiments. The investigations included studies of the overlap between the laser profile and the absorption lines of formaldehyde, saturation effects and the potential occurrence of laser-induced photochemistry. The technique was applied for detection of formaldehyde in an internal combustion engine operated both as a spark ignition engine and as a homogenous charge compression ignition engine.