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41.
Jo?l?Coulon Ilan?Thouvenin Fadi?Aldeek Lavinia?Balan Rapha?l?Schneider 《Journal of fluorescence》2010,20(2):591-597
Highly fluorescent CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) were prepared by an aqueous solution approach
and used as fluorescent labels in detecting yeast cells. Sugars (mannose, galactose or glucose) were adsorbed on CdTe@TGA
QDs and the interaction of these nanoparticles with yeast cells was studied by fluorescence microscopy. Results obtained demonstrate
that galactose and mannose functionalized QDs associate respectively with Kluyveromyces bulgaricus and Saccharomyces cerevisiae yeast strains due to saccharide/lectin specific recognition. Glucose-functionalized CdTe QDs, which are not recognized by
cell lectins, preferentially localize in the bud scars of S. cerevisiae. 相似文献
42.
Alessandra Biancolillo Samantha Reale Martina Foschi Emanuele Bertini Lavinia Antonelli Angelo Antonio DArchivio 《Molecules (Basel, Switzerland)》2022,27(21)
The fatty acid (FA) profiles of 240 samples of ricotta whey cheese made from sheep, goat, cow, or water buffalo milk were analyzed by gas-chromatography (GC). Then, sequential preprocessing through orthogonalization (SPORT) was used in order to classify samples according to the nature of the milk they were made from. This strategy achieved excellent results, correctly classifying 77 (out of 80) validation samples. Eventually, since 36 (over 114) sheep ricotta whey cheeses were PDO products, a second classification problem, finalizing the discrimination of PDO and Non-PDO dairies, was faced. In this case, two classifiers were used, SPORT and soft independent modelling by class analogy (SIMCA). Both approaches provided more than satisfying results; in fact, SPORT properly assigned 63 (of 65) test samples, whereas the SIMCA model accepted 14 PDO individuals over 15 (93.3% sensitivity) and correctly rejected all the other samples (100.0% specificity). In conclusion, all the tested approaches resulted as suitable for the two fixed purposes. Eventually, variable importance in projection (VIP) analysis was used to understand which FAs characterize the different categories of ricotta. Among the 22 analyzed compounds, about 10 are considered the most relevant for the solution of the investigated problems. 相似文献
43.
44.
Marinescu L Mølbach M Rousseau C Bols M 《Journal of the American Chemical Society》2005,127(50):17578-17579
6A,6D-Di-O-(propan-2-on-1,3-diyl) alpha-cyclodextrin-6A,6D-dicarboxylate (2alpha) and 6A,6D-di-O-(propan-2-on-1,3-diyl) beta-cyclodextrin-6A,6D-dicarboxylate (2beta) were found to catalyze the oxidation of aromatic amines in the presence of hydrogen peroxide. The products were the corresponding nitro compounds or in some cases azo-, azoxy-, or other dimerization products. The catalysis was found to follow enzyme kinetics giving a rate increase (kcat/kuncat) of up to 1100 in the best case. 相似文献
45.
Adriana POPA Corneliu-Mircea DAVIDESCU Smaranda ILIESCU Gheorghe ILIA Gheorghe DEHELEAN Lavinia MACARIE Radu TRIF Rumanian Academy Institute of Chemistry M. Viteazul Str. Timisoara Roumania. "Politehnica" University Faculty 《Chinese Journal of Reactive Polymers》2000,(2)
1.INTRODUCTIONThesynthesisofpolymer-supported"onium"salts(ammoniumandphosphonium)(1~5(wasdiscussedindetailduetothewidefieldofutilizationas:polarstationaryphasesforanionchromatography(6(,polymericreagentsfortrans-quaternizationreactions(7,8(,phase-transfercatalysts(9~13(andpolycationicbiocides(14~17(.Manychemicalmaterialssuchasozone,liquidchlorine,sodiumhydrochloride,s.a.,havebeenlargelyusedtosterilizeairandwater.Suchmaterialsrequirespecialequipmentandcarelessusemaycauseenvironmentalpolluti… 相似文献
46.
TMSN3 and PhI(OAc)2 were found to promote high-yield azide substitution of ethers, aldehydes and benzal acetals. The reaction is fast and occurs at zero to ambient temperature in acetonitrile. However, it is essential for the reaction that TMSN3 is added subsequent to the mixture of PhI(OAc)2 and the substrate. A primary deuterium kinetic isotope effect was found for the azidonation of benzyl ethers both with TMSN3-PhI(OAc)2 and with IN3. Also a Hammett free energy relationship study of this reaction showed good correlation with sigma+ constants giving with rho-values of -0.47 for TMSN3-PhI(OAc)2 and -0.39 for IN3. On this basis a radical mechanism of the reaction was proposed. 相似文献
47.
Carlo F. Morelli Arianna Fornili Lavinia Durì Paolo Manitto 《Tetrahedron letters》2005,46(11):1837-1840
The Cl2AlH-mediated ring-opening of 2-substituted cis-4-methyl-5-trifluoromethyl-1,3-dioxolanes was found to occur with regioselective cleavage of the O1-C2 bond by attack of the aluminum hydride from the direction anti to the departing oxygen. This stereochemical outcome, which appears to be unprecedented in the reductive cleavage of chiral acetals by aluminum reagents, is interpreted on the basis of theoretical calculations. 相似文献
48.
Aliphatic and aromatic aldehydes can be converted to acyl azides by treatment with iodine azide at 0-25 degrees C. If the reaction is performed at reflux Curtius rearrangement occurs and carbamoyl azides are obtained in 70-97% yield from the aldehyde. The reaction was shown to have a radical mechanism. 相似文献
49.
[Ge2]4− Dumbbells with Very Short Ge−Ge Distances in the Zintl Phase Li3NaGe2: A Solid‐State Equivalent to Molecular O2
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Lavinia M. Scherf Prof. Dr. Antti J. Karttunen Dr. Oliver Pecher Dr. Pieter C. M. M. Magusin Prof. Dr. Clare P. Grey Prof. Dr. Thomas F. Fässler 《Angewandte Chemie (International ed. in English)》2016,55(3):1075-1079
The novel ternary Zintl phase Li3NaGe2 comprises alkali‐metal cations and [Ge2]4? dumbbells. The diatomic [Ge2]4? unit is characterized by the shortest Ge?Ge distance (2.390(1) Å) ever observed in a Zintl phase and thus represents the first Ge=Ge double bond under such conditions, as also suggested by the (8?N) rule. Raman measurements support these findings. The multiple‐bond character is confirmed by electronic‐structure calculations, and an upfield 6Li NMR shift of ?10.0 ppm, which was assigned to the Li cations surrounded by the π systems of three Ge dumbbells, further underlines this interpretation. For the unperturbed, ligand‐free dumbbell in Li3NaGe2, the π‐ bonding py and pz orbitals are degenerate as in molecular oxygen, which has singly occupied orbitals. The partially filled π‐type bands of the neat solid Li3NaGe2 cross the Fermi level, resulting in metallic properties. Li3NaGe2 was synthesized from the elements as well as from binary reactants and subsequently characterized crystallographically. 相似文献
50.
The role of segregation in the polarized emission from polyfluorene embedded in a liquid crystal
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Lavinia Ghirardini Tersilla Virgili Serena Bolis Jeroen Beeckman Pascal Kockaert Marco Finazzi Michele Celebrano 《Journal of Polymer Science.Polymer Physics》2016,54(16):1558-1563
Polyfluorene (PFO) embedded in a nematic liquid crystal (LC) matrix is investigated. For low PFO weight contents, a homogeneous dispersion is obtained which displays a strong fluorescence anisotropy along the LC director, indicating a significant alignment of the polymeric chains along this direction. Besides, for relatively high PFO weight contents, phase separation takes place. Under these conditions, the sample is composed of micrometer‐sized domains, where the two species are in solution, enclosed by segregated polymeric boundaries. By polarized‐photoluminescence imaging and spectroscopy, it is found that most of the light emission originates from these boundaries and gets strongly pinned along their orientation. Since boundaries are mainly oriented orthogonal to the LC chains, this morphological alignment results in a system in which the orientation of the polarization emission can be predicted and possibly controlled. Conversely, in the homogeneous sample one can obtain a homogeneous emission polarization by controlling the alignment of the LC. These features are potentially relevant for the development of flexible polarization‐sensitive optoelectronic devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1558–1563 相似文献