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71.
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
72.
Peter‐Yong Wang Guillaume Duret Ilan Marek 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(42):15137-15141
The regio‐ and stereoselective preparation of fully substituted and stereodefined silyl enol ethers of ketones and aldehydes through an allyl‐Brook rearrangement is reported. This fast and efficient method proceeds from a mixture of E and Z isomers of easily accessible starting materials. 相似文献
73.
The zinc-catalyzed addition of various alkynes to acylsilanes followed by a Zn-Brook rearrangement and either the Zn-ene-allene or Zn-yne-allene cyclization led to the enantio- and diastereoselective formation of carbocycles in a single-pot operation. 相似文献
74.
We present a variant of the Simplex method which requires on the average at most 2 (min(m, d) + 1)2 pivots to solve the linear program min cT, Ax ≥ b, x ≥ 0 with A Rm×d. The underlying probabilistic distribution is assumed to be invariant under inverting the sense of any subset of the inequalities. In particular, this implies that under Smale's spherically symmetric model this variant requires an average of no more than 2(d + 1)2 pivots, independent of m, where d ≤ m. 相似文献
75.
Dr. Xu Chen Kaushalendra Patel Prof. Dr. Ilan Marek 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(3):e202212425
An efficient method for the stereoselective construction of tertiary C−O bonds via a stereoinvertive nucleophilic substitution at the quaternary carbon stereocenter of cyclopropyl carbinol derivatives using water, alcohols and phenols as nucleophiles has been developed. This substitution reaction proceeds under mild conditions and tolerates several functional groups, providing a new access to the stereoselective formation of highly congested tertiary homoallyl alcohols and ethers. 相似文献
76.
Luo G Malkova S Pingali SV Schultz DG Lin B Meron M Benjamin I Vanysek P Schlossman ML 《The journal of physical chemistry. B》2006,110(10):4527-4530
Synchrotron X-ray reflectivity is used to study the electron density as a function of depth through the bulk nitrobenzene-water interface at four different temperatures. The measured interfacial width differs from the predictions of capillary wave theory with a progressively smaller deviation as the temperature is raised. Computer simulations suggest the presence of both molecular layering and dipole ordering parallel to the interface. Either layering or a bending rigidity, that can result from dipole ordering, can explain these measurements. 相似文献
77.
Overcoming the inherent difficulty to prepare quaternary carbon stereogenic centers, the diastereo‐ and enantioselective preparation of acyclic carbon backbones possessing vicinal quaternary and tertiary stereogenic centers (i.e. in a 1,2‐relationship) causes distorted geometries and represents a very acute problem in organic synthesis. Several approaches are discussed in this minireview underlining the challenges illustrated by the rather limited number of approaches available to practitioners. 相似文献
78.
Itai Massad Heiko Sommer Ilan Marek 《Angewandte Chemie (International ed. in English)》2020,59(36):15549-15553
An in situ generated cationic Ir‐catalyst isomerizes simple allylic silyl ethers into valuable, fully substituted aldehyde‐derived silyl enol ethers. Importantly, by judicious choice of substrate, either of the two possible stereoisomers of a given enolate derivative is accessible with complete stereoselectivity. One‐pot isomerization‐aldol and isomerization‐allylation processes illustrate the synthetic utility of this method. 相似文献
79.
Ilan Goldfarb R. Stanley Williams 《Applied Physics A: Materials Science & Processing》2014,114(2):287-289
We compare our photoemission spectra with the calculated energy spectra of oxygen vacancies in Ta oxide to identify the defects responsible for the formation of a band in the gap of a Ta oxide-based memristor. We have previously explained transitions between high and low resistance states in a memristor conducting channel under bias reversal by accumulation and depletion of oxygen in the channel. Oxidation leads to a higher resistance due to sparser conduction centers for the electrons to hop between. Here, we show that they are likely due to neutral oxygen vacancies located at ‘in-plane’ sites of the Ta–O polyhedra. 相似文献
80.
Sagi Frishman Alexander Gumennik Har’el Ilan Aharon J. Agranat 《Applied physics. B, Lasers and optics》2014,115(1):143-147
Electro-optically tunable transmission grating was imprinted in potassium lithium tantalate niobate by irreversible spatial patterning of the dielectric constant. While embedded into waveguided architecture, it provides a reliable and versatile building block for opto-electronic circuitry, capable of both active switching and multiplexing. Realization of such a block is critical for the fabrication of integrated photonic circuits in electro-optic substrates by means of Refractive Index Engineering by fast ion implantation. 相似文献