35 research outputs found

    Is It Hop? Identifying Hop Fibres in a European Historical Context

    Get PDF
    Hop (Humulus lupulus L .) is an ancient perennial crop plant, native to the Northern Hemisphere. The archaeological evidence dates back to at least the sixth century ad in Europe. Hop has been used for beer brewing, in sleeping draughts, as bedding and for antibacterial purposes. Less known is that hop fibres have also been used for textiles and paper. However, it is difficult to distinguish hop from other bast fibres. Here, we present a set of fibre features, which, when found together in an archaeological/historical material within a European context, provide a strong indication that the fibres are hop.publishedVersio

    Free-Volume Evolution of 1-Propanol Confined in Variously Filled Regular Mesopores of SBA-15 Matrix

    No full text
    The free-volume of 1-propanol (1-PrOH) confined in a regular mesoporous SBA-15 matrix was investigated by desorption experiment at room temperature and over a wide temperature range, from 15 K up to 350 K, for four different contents of 1-PrOH in the pores. The gradual desorption of 1-PrOH from the mesopores as well as the free volume temperature dependences have shown that the polar molecules of 1-PrOH located at the inner polar surface of the SBA-15 matrix are more strongly bound to the matrix surface. The subsequent discussion of the annihilation and free-volume characteristics follows

    Is It Hop? Identifying Hop Fibres in a European Historical Context

    No full text
    Hop (Humulus lupulus L .) is an ancient perennial crop plant, native to the Northern Hemisphere. The archaeological evidence dates back to at least the sixth century ad in Europe. Hop has been used for beer brewing, in sleeping draughts, as bedding and for antibacterial purposes. Less known is that hop fibres have also been used for textiles and paper. However, it is difficult to distinguish hop from other bast fibres. Here, we present a set of fibre features, which, when found together in an archaeological/historical material within a European context, provide a strong indication that the fibres are hop

    Hydride mobility in trinuclear sulfido clusters with the core [Rh 3(μ-H)(μ3-S)2]: Molecular models for hydrogen migration on metal sulfide hydrotreating catalysts

    Get PDF
    The treatment of [{Rh(μ-SH){P(OPh)3}2} 2] with [{M(μ-Cl)(diolef)}2] (diolef=diolefin) in the presence of NEt3 affords the hydrido-sulfido clusters [Rh 3(μ-H)(μ3-S)2(diolef){P(OPh) 3}4] (diolef=1,5-cyclooctadiene (cod) for 1, 2,5-norbornadiene (nbd) for 2, and tetrafluorobenzo[5,6]bicyclo[2.2.2]octa-2,5, 7-triene (tfb) for 3) and [Rh2Ir(μ-H)(μ3-S) 2(cod){P(OPh)3}4] (4). Cluster 1 can be also obtained by treating [{Rh(μ-SH){P(OPh)3}2}2] with [{Rh(μ-OMe)(cod)}2], although the main product of the reaction with [{Ir(μ-OMe)(cod)}2] was [RhIr2(μ-H) (μ3-S)2(cod)2{P(OPh)3} 2] (5). The molecular structures of clusters 1 and 4 have been determined by X-ray diffraction methods. The deprotonation of a hydrosulfido ligand in [{Rh(μ-SH)(CO)(PPh3)}2] by [M(acac)(diolef)] (acac=acetylacetonate) results in the formation of hydrido-sulfido clusters [Rh3(μ-H)(μ3-S)2(CO)2(diolef) (PPh3)2] (diolef=cod for 6, nbd for 7) and [Rh 2Ir(μ-H)(μ3-S)2(CO)2(cod) (PPh3)2] (8). Clusters 1-3 and 5 exist in solution as two interconverting isomers with the bridging hydride ligand at different edges. Cluster 8 exists as three isomers that arise from the disposition of the PPh3 ligands in the cluster (cis and trans) and the location of the hydride ligand. The dynamic behaviour of clusters with bulky triphenylphosphite ligands, which involves hydrogen migration from rhodium to sulfur with a switch from hydride to proton character, is significant to understand hydrogen diffusion on the surface of metal sulfide hydrotreating catalysts.Financial support from Ministerio de Ciencia e Innovación (MICINN/ FEDER) is gratefully acknowledged (Projects: CTQ2006-03973 and CTQ2009-08089).Peer Reviewe

    Spin probe interaction and mobility in confined cyclohexane: effects of pore size and pore surface composition of silica gel matrices

    No full text
    The spectral behavior of the spin probe TEMPO in the bulk cyclohexane (CHX) and its confined states in a series of silica gels (SG) using ESR is reported. The spectral parameter Azz’ and the characteristic ESR temperature T(50G) of slow to fast regime transition of TEMPO change dramatically in the virgin SG-SIL‘s compared to the bulk CHX sligtly depending on the pore size. These observations result from the interrelation between the mutual interaction of the TEMPO with the SG‘s and the altered phase behavior of the CHX from DSC. This is supported by the modified (silanized) SG matrices

    Pb and Zn and the onset of Anthropocene in floodplain sediments: How and why to quantify weak contamination?

    No full text
    In our laboratory we work on the quantification of heavy metal pollution in fluvial sediments of which sedimentological description, facial assignment, post-depositional stability and dating are incomplete or missing. Without such fundamental knowledge the only robust information is apparently the absolute concentration of heavy metals. Due to local geochemical differences and heavy metal sorting by fluvial transport and pedogenesis, the actual level of anthropogenic contamination is usually considered inconclusive when the enrichment factor E

    Synthetic inhibitors of CDKs induce different responses in androgen sensitive and androgen insensitive prostatic cancer cell lines

    No full text
    Aims: Because of the high prevalence of prostatic cancer and the limitations of its treatment, enormous effort has been put into the development of new therapeutic modalities. One potential tool is the use of cyclin dependent kinase (CDK) inhibitors, which are based on the trisubstituted derivatives of purine. The aim of this study was to analyse alterations of the regulatory pathways in both androgen sensitive and androgen insensitive prostatic cancer cell lines (LNCaP and DU-145, respectively) after blockage of the cell cycle by the synthetic CDK inhibitors, olomoucine and bohemine. Methods: The effects of olomoucine and bohemine were studied on the following parameters: (1) cell proliferation, by measurement of DNA content; (2) viability, by the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) and/or XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide) test; and (3) the expression of p53, pRB, Bcl-2, Bax, p16, p21, p27, cyclins A, B, D1, E, p34(cdc2), and the androgen receptor (AR), by western blot analysis. Results: Both olomoucine and bohemine were potent inhibitors of growth and viability; however, bohemine was two to three times more effective than olomoucine. The sensitivity of LNCaP cells to both agents was significantly higher. After treatment, both cell lines revealed quite different spectra of protein expression. Conclusions: These results indicate the existence of specific cell cycle regulating pathways in both cell lines, which may be associated with both p53 and AR status. CDK inhibitors exhibited valuable secondary effects on the expression of numerous regulators and thus may modulate the responsiveness of tumour cells to treatment, including treatment with hormone antagonists
    corecore