Study of Catalytic Activity of the New Nanohybrid Material Based on Gold Nanoparticles and 1,4-bis(Terpyridine-4'-yl)Benzene

The paper describes the synthesis of composite material consisting of 1,4-bis(terpyridine-4'-yl)benzene microcrystals and gold nanoparticles with an average size of 15 nm adsorbed on their surfaces. The nanohybrid material is obtained by the deposition of pre-synthesized nanoparticles on the surface of the organic compound. Mass content of gold in the obtained material is determined by the thermogravimetrical analysis. Catalytic reduction of para-nitrophenol is spectrophotometrically studied. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3512

Heterogeneous catalysts and process for reductive dechlorination of polychlorinated hydrocarbons

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Heterogeneous catalysts and process for reductive dechlorination of polychlorinated hydrocarbons

IN STAMP

Characterisation of neotropical savanna and seasonally dry forest ecosystems by their modern pollen rain

At present there is uncertainty over the response of neotropical ecosystems to the climatic changes of the Quaternary. The majority of vegetation reconstructions from the region are derived from fossil pollen records extracted from lake sediments. However, the interpretation of these records is restricted by limited knowledge of the contemporary relationships between the vegetation and pollen rain of neotropical ecosystems, especially for more open vegetation such as savanna and dry forest. This research aims to improve the interpretation of these records by investigating the relationship between the vegetation and modern pollen rain of different savanna and seasonally dry tropical forest (SDTF) ecosystems in Bolivia using artificial pollen traps and surface lake sediments to analyse the modern pollen rain. Vegetation data is used to identify taxa that are floristically important within the different ecosystems and to allow modern pollen/vegetation ratios to be calculated. The modern pollen rain from the upland savanna is dominated by Moraceae/Urticaceae (35.1%), Poaceae (29.6%), Alchornea (6.1%) and Cecropia (4.1%), whilst the seasonally-inundated savanna sites are dominated by Moraceae/Urticaceae (30.7%), Poaceae (19.5%), Cyperaceae (14.0%) and Cecropia (7.9%). These two different savanna ecosystems are only slightly differentiated by their modern pollen rain. The main taxa in the modern pollen rain of the upland SDTF are Moraceae/Urticaceae (25.8%), Cecropia (10.5%), Acalypha (7.6%) and Combretaceae/Melastomataceae (6.7%). Seasonally-inundated SDTF is dominated by Cecropia pollen to the extent that it was removed from the pollen sum and the main non-Cecropia pollen types are Moraceae/Urticaceae (39.0%), unknown type df 61 (6.4%), Asteraceae (6.3%), Celtis (6.0%) and Physocalymma scaberrimum (4.9%). These two SDTF ecosystems are well differentiated by their modern pollen rain, implying that they may be defined in fossil pollen records. The modern pollen rain obtained from the surface lake samples is generally complementary to that obtained from the artificial pollen traps for a given ecosystem. All sites have a high Moraceae/Urticaceae pollen signal due to effective dispersal of this pollen type from areas of evergreen forest in close proximity to the study sites. The savanna sites show lower Poaceae percentages than have been previously reported in the literature by some authors and this raises the possibility than the extent of this ecosystem in the past may have been underestimated. Modern pollen/vegetation ratios show that many key vegetation types are absent/under-represented within the modern pollen rain.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Heterogeneous catalysts and process for reductive dechlorination of polychlorinated hydrocarbons

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Paramagnetic centers in detonation nanodiamonds studied by CW and pulse EPR

Dispersed detonation nanodiamonds have been studied by continuous-wave (CW) and pulse EPR techniques. The spectrum of bulk radicals (g = 2.0025 +/- 0.0002, a Lorentz line shape with Delta H-pp = 0.95 +/- 0.05 mT) dominated in CW EPR and prevented to record spectra from other paramagnetic species. The pulse EPR-spectrum was the superposition of the distorted P1-center spectrum with parameters (g = 2.0025, A(xx) = 2.57 mT, A(yy) = 3.08 mT, A(zz) = 4.07 mT), the H1-center spectrum (g = 2.0028) and the single line (g = 2.0025, DHpp = 0.40 +/- 0.05 mT) from other centers which may be assigned to surface radicals. The concentration of P1-centers has been estimated by CW EPR as 2 +/- 1 ppm N.Original Publication:A.V. Fionov, Anders Lund, Weimin Chen, N.N. Rozhkova, Irina Buyanova, G.I. Emelyanova, L.E. Gorlenko, E.V. Golubina, E.S. Lokteva, E. Osawa and V.V. Lunin, Paramagnetic centers in detonation nanodiamonds studied by CW and pulse EPR, 2010, Chemical Physics Letters, (493), 04-Jun, 319-322.http://dx.doi.org/10.1016/j.cplett.2010.05.050Copyright: Elsevier Science B.V., Amsterdam.http://www.elsevier.com