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Europium (Eu+) ions were confined in a Paul trap and detected by non-destructive method. Storage time of Eu+ ions achieved in vacuum was improved by orders of magnitude employing buffer gas cooling. The experimentally detected signal
was fitted to the ion response signal and the total number of ions trapped was estimated. It is found that the peak signal
amplitude as well as the product of FWHM and the peak signal amplitude is proportional to the total number of trapped ions.
The trapped ion secular frequency was swept at different rates and its effect on the absorption line profile was studied both
experimentally and theoretically. 相似文献
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We present a novel approach to generating radially and azimuthally polarized vector beams that utilize an interferometer constructed from two identical diffractive optical elements. The measured polarization properties of four vector beam states and their phase relationships are in good agreement with theoretical expectations. This interferometer is passively phase stable and robust, making it suitable for linear and nonlinear optical (superresolution) microscopy. 相似文献
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Eliene O Kozlowski Paula C Lima Cristina P Vicente Tito Lotufo Xingfeng Bao Kazuyuki Sugahara Mauro SG Pavão 《BMC biochemistry》2011,12(1):1-2
After the publication of the work entitled "Dermatan sulfate in tunicate phylogeny: Order-specific sulfation pattern and the effect of [→4IdoA(2-Sulfate)β-1→3GalNAc(4-Sulfate)β-1→] motifs in dermatan sulfate on heparin cofactor II activity", by Kozlowski et al., BMC Biochemistry 2011, 12:29, we found that the legends to Figures 2 to 5 contain serious mistakes that compromise the comprehension of the work. This correction article contains the correct text of the legends to Figures 2 to 5. 相似文献
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We propose an approach to optical microscopy that enables full control over the three-dimensional polarization vector at the focal spot of a high-numerical-aperture lens. The input field to the lens is linearly polarized and no polarization optics are needed. This technique utilizes the azimuthal spatial degree of freedom of the input field. We find that only a small set of low-order azimuthal spatial harmonics contributes to the focused field on axis, and a simple transformation exists between the linear vector space of these harmonics and the three-dimensional polarization-vector space. Controlling the relative complex weights of these azimuthal harmonics produces any desired three-dimensional state of polarization. 相似文献
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Martin M. Kimani Don VanDerveer Julia L. Brumaghim 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(6):m208-m210
In the title compound, catena‐poly[diselanylbis(1,3‐dimethyl‐1H‐imidazol‐3‐ium) [μ3‐chlorido‐tetra‐μ2‐chlorido‐tricuprate(I)]], {(C10H16N4Se2)[Cu3Cl5]}n, the diselenide dication is stabilized by catena‐[Cu3Cl5]2− anions which associate through strong Cu—Cl bonds [average length = 2.3525 (13) Å] to form polymeric chains. The polymeric [Cu3Cl5]2− anion contains crystallographically imposed twofold rotation symmetry, with distorted trigonal‐planar and tetrahedral geometries around the two symmetry‐independent Cu atoms. Likewise, the Se—Se bond of the cation is centered on a twofold rotation axis. 相似文献
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We examine a method to mimic active sites in proteins by chemical imprinting of p-valent templates in heteropolymer gels. Previous studies have confirmed successful formation of sites by adsorption of targets with p >/= 2 contacts. We investigate the recovery of sites with p = 2 imprinted by lead methacrylate Pb(MAAc)(2) (placing two carboxyl groups in close proximity). The improved binding ability of gels with more cross-links, and the relative insensitivity to changes in gel volume contradict simple theory. We conclude that adsorber pairs are predominantly located on the same polymer chain, posing a challenge to mimicking protein-like function. 相似文献
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Summary: A novel hydroxyl‐functionalised initiator for atom transfer radical polymerisation (ATRP) was synthesised by esterification reaction of a non‐reducing sugar, meso‐inositol. Due to steric hindrance, one of the six hydroxyl groups present in the sugar was not derivatised to the corresponding 2‐bromoisobutyrate. The macroinitiator was used in ambient temperature ATRP of a hydrophobic monomer, methyl methacrylate (MMA) and a hydrophilic monomer, oligoethylene glycol methacrylate (OEGMA) using tri(ethylene glycol) monomethyl ether (TEGMME) as the polymerisation solvent and CuCl/CuCl2/PMDETA as the catalytic system. Under these conditions, polymerisation proceeded on to high conversion while maintaining low polydispersity giving well‐defined five‐arm star polymers. Hydrolysis under basic conditions was carried out to deduce the number of linear chains that were attached to the sugar.
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