Electron energy loss spectroscopic study of Cr(CO)6, Mo(CO)6 and W(CO)6 in the vapour phase

Electron energy loss spectra (EELS) of Cr, Mo and W hexacarbonyls in the vapour phase are reported. Most of the bands observed are similar to those in optical spectra, but the two high energy transitions in the 9·8–11·2 eV region are reported here for the first time. Based on the orbital energies from the ultraviolet photoelectron spectra and the electronic transition energies from EELS and earlier optical studies, the molecular energy level schemes of these molecules are constructed.

4-Azidomethyl-7-methyl-2-oxo-2H-chromene-6-sulfonyl azide

In the title compound, C11H8N6O4S, the plane of the coumarin aromatic ring is twisted by 17.2 (2)degrees with respect to the plane of the azide group bound to the methylene substituent, whereas it is twisted by 83.2 (2)degrees to the plane of the azide attached to the sulfonyl group. The crystal structure is stabilized by weak C-H center dot center dot center dot O interactions, leading to the formation of dimers with R-2(2)(12) graph-set motifs. These dimers are further linked by weak S-O center dot center dot center dot pi and pi-pi contacts centroid-centroid distance = 3.765 (2) angstrom], leading to the formation of a layered structure.

(2R,3R,4aS,6S,7S,8aS)-4a-Fluoro-8a-hydroxyperhydronaphthalene-2,3,6,7-te trayl tetraacetate

The title compound, C18H25FO9, exhibits a similar unit cell and packing to the alpha polymorph of axial 4a,8a-dihydroxyperhydronaphthalene-2,3,6,7-tetrayl tetraacetate. The carbonyl O atoms of two of the four acetate groups in the molecule are disordered over two sites with occupancy ratios of 0.59 (4):0.41 (4) and 0.57 (6):0.43 (6). Crystal packing is effected via intermolecular O-H center dot center dot center dot O hydrogen bonds, which link the tetraacetate molecules into tapes along the c axis.

Underemployment and part-time work in the Nordic countries

84 s.

Mapping Road Infrastructure in Developing Countries Applying Remote Sensing and GIS - The Case of the Taita Hills, Kenya

Road transport and infrastructure has a fundamental meaning for the developing world. Poor quality and inadequate coverage of roads, lack of maintenance operations and outdated road maps continue to hinder economic and social development in the developing countries. This thesis focuses on studying the present state of road infrastructure and its mapping in the Taita Hills, south-east Kenya. The study is included as a part of the TAITA-project by the Department of Geography, University of Helsinki. The road infrastructure of the study area is studied by remote sensing and GIS based methodology. As the principal dataset, true colour airborne digital camera data from 2004, was used to generate an aerial image mosaic of the study area. Auxiliary data includes SPOT satellite imagery from 2003, field spectrometry data of road surfaces and relevant literature. Road infrastructure characteristics are interpreted from three test sites using pixel-based supervised classification, object-oriented supervised classifications and visual interpretation. Road infrastructure of the test sites is interpreted visually from a SPOT image. Road centrelines are then extracted from the object-oriented classification results with an automatic vectorisation process. The road infrastructure of the entire image mosaic is mapped by applying the most appropriate assessed data and techniques. The spectral characteristics and reflectance of various road surfaces are considered with the acquired field spectra and relevant literature. The results are compared with the experimented road mapping methods. This study concludes that classification and extraction of roads remains a difficult task, and that the accuracy of the results is inadequate regardless of the high spatial resolution of the image mosaic used in this thesis. Visual interpretation, out of all the experimented methods in this thesis is the most straightforward, accurate and valid technique for road mapping. Certain road surfaces have similar spectral characteristics and reflectance values with other land cover and land use. This has a great influence for digital analysis techniques in particular. Road mapping is made even more complicated by rich vegetation and tree canopy, clouds, shadows, low contrast between roads and surroundings and the width of narrow roads in relation to the spatial resolution of the imagery used. The results of this thesis may be applied to road infrastructure mapping in developing countries on a more general context, although with certain limits. In particular, unclassified rural roads require updated road mapping schemas to intensify road transport possibilities and to assist in the development of the developing world.

Annales Societatis zoologicae-botanicae Fennicae Vanamo tom. 6

Tiivistelmien kieli suomi.

Insights into conformational and packing features in a series of aryl substituted ethyl-6-methyl-4-phenyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate

The supramolecular structures of eight aryl protected ethyl-6-methyl-4-phenyl-2-oxo-1,2,3,4-tetrahydropyrimidine- 5-carboxylates have been analyzed to determine the role of different functional groups on the molecular geometry, conformational characteristics and the packing of these molecules in the crystal lattice. Out of these the para fluoro substituted compound on the aryl ring exhibits conformational polymorphism, due to the different conformation of the ester moiety. This behaviour has been characterized using both powder and single-crystal X-ray diffraction, optical microscopy and differential scanning calorimetry performed on both these polymorphs. The compounds pack via the cooperative interplay of strong N-H center dot center dot center dot O=C intermolecular dimers and chains forming a sheet like structure. In addition, weak C-H center dot center dot center dot O=C and C-H center dot center dot center dot pi interactions impart additional stability to the crystal packing.

Potassamide induced in situ alkylation of 5,6-dihydroisoquinolines: Structure of products

Potassamide induced in situ alkylation of 1-alkyl- 4-cyano-3-methoxy-5,6-dihydroisoquinolines (2a & 2b) with alkyl iodides (CH3I, CH3CH2I & cyclohexyl iodide) gave the 5-alkyl- and 5,9-dialkyl-5,6-dihydroisoquinolines (4–ad & 3a–e), isoquinoline derivatives, (5a–b) and diastereomeric mixture of 4- alkyl-1,2,3,4-tetrahydroisoquinolin-3(2H)-ones (6a–e & 6′a–e). Structures were assigned on the basis of spectral data [Mass, 1H & 13C NMR, 2D NOESY & HC-COLOC]. Amide induced in situ alkylation of compounds 3a and 4a with CH3I gave in almost quantitative yield the dimethylated compounds 3d and 3a respectively. While KNH2/liq.NH3 methylation of 1,2- dihydroisoquinoline, 1 with CH3I gave the mixture of compounds, 6a & 6′a and the isoquinoline derivative 5a, NaH/benzene reaction of 1 with CH3I gave exclusively 5a. N-methylation of the mixture of compounds 6a & 6′a with NaH/CH3I gave the methylated derivatives, 7 & 8. A suitable mechanism has been proposed for the formation of products.

Stereospecific construction of multiple contiguous quaternary carbons. Total synthesis of (±)-cis,anti,cis-1,8,12,12-tetramethyl-4-oxatricyclo[6.4.0.02,6]dodecan-3-ol, a thapsane isolated from Thapsia villosa var minor

The details of the first total synthesis of a natural thapsane lg containing three contiguous quaternary carbon atoms, starting from cyclogeraniol (9) '5 described. The Claisen rearrangement of 9 with methoxypropene in the presence of a catalytic amount of propionic acid produced ketone 10. Rhodium acetate-catalyzed intramolecular cyclopropanation of a-diazo-&keto ester 12, obtained from 10 via 8-keto ester 8, furnished cyclopropyl keto ester 7. Lithium in liquid ammonia reductive cleavage of cyclopropyl compound 7 gave a 1:l mixture of hydrindanone 6 and keto1 13. Wittig methylenation of 6 furnished ester 21. Epoxidation of 21, followed by BF3-OEt2-catalyzed rearrangement of epoxide 23 afforded hemiacetal 25. Treatment of hemiacetal 25 with triethylsilane in trifluoroacetic acid furnished lactone 22, a degradation product of various thapsanes. Finally, DIBAH reduction of lactone 22 generated the thapsane

Formation of a single, rotated-Brass (1 1 0)< 5 5 6 > texture by hot cross-rolling of an Al-Zn-Mg-Cu-Zr alloy

The present work describes the evolution of a strong, single-component rotated-Brass ((1 1 0) < 5 5 6 >) texture in an Al-Zn-Mg-Cu-Zr alloy by an uneven hot cross-rolling with frequent interpass annealing. This texture development is unique because hot rolling of aluminum alloys results in orientation distribution along the ``beta-fibre''. It has been demonstrated that the deformation by cross-rolling of a partially recrystallized grain structure having rotated-Cube and Goss orientations, and the recrystallization resistance of near-Brass-oriented elongated grains play a critical role in development of this texture. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Synthesis and Isolation of 5,6-Dihydro-4H-1,3-Oxazine Hydrobromides by Autocyclization of N-(3-Bromopropyl)amides

5,6-Dihydro-4H-1,3-oxazine hydrobromides have been synthesized by the nucleophilic autocyclo-O-alkylation of N-(3-bromopropyl)amides under neutral conditions in chloroform. It is found that electron-donating amide alpha-substituents influence the autocyclization efficiency.

META-NORD: Towards Sharing of Language Resources in Nordic and Baltic Countries

This paper introduces the META-NORD project which develops Nordic and Baltic part of the European open language resource infrastructure. META-NORD works on assembling, linking across languages, and making widely available the basic language resources used by developers, professionals and researchers to build specific products and applications. The goals of the project, overall approach and specific focus lines on wordnets, terminology resources and treebanks are described. Moreover, results achieved in first five months of the project, i.e. language whitepapers, metadata specification and IPR, are presented.