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51.
The resitivity change of ultra thin metals under air exposure is used for vacuum or inert gas packaging control. In order to reach low cost, single use applications, few nm thin Aluminum layers were deposited on PET substrates and combined with wireless electronic readout circuitry.The sensor respose is characterized by resistance changes and explained in terms of multiphase diffusion mechanisms which are very sensitive to technological parameters. 相似文献
52.
53.
Irving C. Bull 《Analytical and bioanalytical chemistry》1902,41(11):653-674
54.
Ohne Zusammenfassung 相似文献
55.
The adsorption of potassium on the Cu(111) surface in a (2×2) pattern has been simulated with all-electron full-potential
density functional calculations. The top site is found to be the preferred adsorption site, with the other highly symmetric
adsorption sites being nearly degenerate. The bond length from potassium to the nearest copper atom is computed to be 2.83
?. Population analysis and density of states indicate that there is no evidence for covalent bonding so that the binding mechanism
appears to be a metallic bond.
Received 11 April 2001 相似文献
56.
Irving C. Bull 《Fresenius' Journal of Analytical Chemistry》1902,41(11):653-674
Ohne ZusammenfassungAus dem Englischen übersetzt von der Redaction. 相似文献
57.
A new flow-through system for the production of [11C]phosgene, a versatile labelling agent in radiochemistry for PET, is described. Cyclotron-produced [11C]CH4 is mixed with Cl2 and converted into [11C]CCl4 by passing the mixture through an empty quartz tube at 510 °C. The outflow is directed through a Sb-filled guard that takes out Cl2 and then, without intentional O2 addition, through a second empty quartz tube at 750 °C, giving rise to [11C]phosgene in 30–35% radiochemical yield. 相似文献
58.
Wong WW Vak D Singh TB Ren S Yan C Jones DJ Liaw II Lamb RN Holmes AB 《Organic letters》2010,12(21):5000-5003
A new class of self-assembling hexa-peri-hexbenzocoronene (HBC)-fullerene hybrid materials has been synthesized and characterized. Photoluminescence experiments indicate that energy transfer processes can be tuned in these donor-acceptor systems by varying the length and nature of the linker group. In preliminary device testing, ambipolar charge transport behavior is observed in organic field effect transistors, while single active component organic photovoltaic devices consisting of these materials achieved a maximum external quantum efficiency of 30%. 相似文献
59.
Erika Cerutti Annelaure Damont Frédéric Dollé Simona Baroni Silvio Aime 《Magnetic resonance in chemistry : MRC》2013,51(2):116-122
DPA‐713 is the lead compound of a recently reported pyrazolo[1,5‐a]pyrimidineacetamide series, targeting the translocator protein (TSPO 18 kDa), and as such, this structure, as well as closely related derivatives, have been already successfully used as positron emission tomography radioligands. On the basis of the pharmacological core of this ligands series, a new magnetic resonance imaging probe, coded DPA‐C6‐(Gd)DOTAMA was designed and successfully synthesized in six steps and 13% overall yield from DPA‐713. The Gd‐DOTA monoamide cage (DOTA = 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid) represents the magnetic resonance imaging reporter, which is spaced from the phenylpyrazolo[1,5‐a]pyrimidineacetamide moiety (DPA‐713 motif) by a six carbon‐atom chain. DPA‐C6‐(Gd)DOTAMA relaxometric characterization showed the typical behavior of a small‐sized molecule (relaxivity value: 6.02 mM?1 s?1 at 20 MHz). The good hydrophilicity of the metal chelate makes DPA‐C6‐(Gd)DOTAMA soluble in water, affecting thus its biodistribution with respect to the parent lipophilic DPA‐713 molecule. For this reason, it was deemed of interest to load the probe to a large carrier in order to increase its residence lifetime in blood. Whereas DPA‐C6‐(Gd)DOTAMA binds to serum albumin with a low affinity constant, it can be entrapped into liposomes (both in the membrane and in the inner aqueous cavity). The stability of the supramolecular adduct formed by the Gd‐complex and liposomes was assessed by a competition test with albumin. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
60.