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101.
Orazio A. Attanasi Paolino Filippone Amedeo Mei Francesca Romana Perrulli Franco Serra-zanetti 《合成通讯》2013,43(11):1411-1421
Pyrrole and several its derivatives have been subjected to extensive chemical investigations, while substituted 1-aminopyrroles remain a class of compounds about which relatively little is known due to the far from trivial problem sposed by their syntheis. In fact, 1-aminopyrroles appear to be prepared mainly by direct reactionfrom conjugated azoalkenes,2 that unfortunately represent a class of relatively little 相似文献
102.
Nováková Kateřina Navrátil Tomáš Šestáková Ivana Le Minh Phuong Vodičková Hana Zámečníková Brigita Sokolová Romana Bulíčková Jana Gál Miroslav 《Monatshefte für Chemie / Chemical Monthly》2015,146(5):819-829
Monatshefte für Chemie - Chemical Monthly - The present study is focused on characterization and elucidation of transport processes of the environmentally important element cadmium across... 相似文献
103.
Magdaléna Hromadová Viliam Kolivoška Miroslav Gál Lubomír Pospíšil Romana Sokolová Michal Valášek 《Journal of inclusion phenomena and macrocyclic chemistry》2011,70(3-4):461-469
An extended viologen dication 1, containing one viologen subunit, was used as a model for the inclusion complex formation between cyclodextrin (CD) molecules and molecular wires comprising several subunits. UV–Vis and fluorescence spectroscopic measurements confirmed the formation of two types of the inclusion complexes 1:1 and 2:1 between αCD and 1 in the aqueous solution containing 20% of ethanol. The complex formation constants were obtained from the fluorescence spectral changes: K a = 25 ± 3 mM?1 for [αCD–1] complex and K a = 0.21 ± 0.07 mM?2 for [(αCD)2–1] complex, respectively. Cyclodextrins βCD and γCD do not form the inclusion complexes with 1 in these aqueous solutions. The time-dependent differential capacitance measurements confirmed the adsorption of 1 in the form of a complex at the electrode/electrolyte interface. These studies were conducted with the aim to find the most suitable CD cavity that would separate individual molecular wires from each other on the electrode/electrolyte interface. 相似文献
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Mihaela Badea Florentina Pătraşcu Romana Cerc Korošec Peter Bukovec Monica Raita Mariana Carmen Chifiriuc Luminiţa Măruţescu Coralia Bleotu Bruno Velescu Dana Marinescu Valentina Uivarosi Rodica Olar 《Journal of Thermal Analysis and Calorimetry》2014,115(2):1183-1193
Five types of fibrous assemblies, namely, polyester, wool, cashmere, kapok, and goose down, were tested for their heat-insulating properties in the natural state using the apparatus developed by the authors. The influences of bulk density, fiber type, fiber arrangements, and compression on the heat-insulating properties of the fibrous assemblies was examined systematically. The results show that kapok assembly with low bulk density, goose down assembly with high bulk density and the randomly arranged fibrous assembly demonstrated the best heat-insulating property; however, considering practical use and the influence of compression, kapok assembly and fibrous assemblies arranged in the form of fiber balls exhibited the most stable and optimum heat-insulating property. The Daryabeigi heat-transfer model that considers fiber contact and scattering effect was used to calculate the heat-insulating properties of the five fibrous assemblies. A similar model was developed by Fanworth, which neglected the fiber and the scattering effect. Comparison of the two models showed that the Daryabeigi model was more accurate in predicting the heat-insulating properties of fibrous assemblies. 相似文献
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Baldoli C Rigamonti C Maiorana S Licandro E Falciola L Mussini PR 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(15):4091-4100
We have designed and synthesised a new organometallic molecule containing three ferrocene groups for use as a highly sensitive electrochemical marker in biological assays. This trisferrocene derivative was conjugated to different PNA monomers, and the electrochemical activities of the conjugates were extensively investigated in organic solvents, in view of their potential diagnostic applications. The results showed that the introduction of a trisferrocene unit on the PNA monomer triples the current signal in comparison with the monoferrocene-labelled one. Despite their greater molecular complexity, trisferrocene-conjugated PNA monomers are even more electrochemically active than the reference ferrocene. By using differential pulse voltammetry (DPV), the detection limit can reach 10(-8) M in acetonitrile solution. These results are a good premise for the use of the trisferrocene unit as an effective electrochemical probe for biomolecules. 相似文献
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Romana Mikšová Pavel Horák Václav Holý Anna Macková 《Surface and interface analysis : SIA》2019,51(11):1113-1120
A Si crystal layer on SiO2/Si was implanted using 0.4-MeV Kr+, Ag+, and Au+ at ion fluences of 0.5 × 1015 to 5.0 × 1015 cm−2. Subsequent annealing was performed at temperatures of 450° and 800° for 1 hour. The structural modification in a Si crystal influences ion beam channelling phenomena; therefore, implanted and annealed samples were investigated by Rutherford backscattering spectrometry under channelling (RBS-C) conditions using an incident beam of 2-MeV He+ from a 3-MV Tandetron in random or in aligned directions. The depth profiles of the implanted atoms and the dislocated Si atom depth profiles in the Si layer were extracted directly from the RBS measurement. The damage accumulation and changes in the crystallographic structure before and after annealing were studied by X-ray diffraction (XRD) analysis. Lattice parameters in modified silicon layers determined by XRD were discussed in connection to RBS-C findings showing the crystalline structure modification depending on ion implantation and annealing parameters. 相似文献