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21.
Mikhail V. Gorshkov David M. Good Yaroslav Lyutvinskiy Hongqian Yang Roman A. Zubarev 《Journal of the American Society for Mass Spectrometry》2010,21(11):1846-1851
Ion storage in an electrostatic trap has been implemented with the introduction of the Orbitrap Fourier transform mass spectrometer
(FTMS), which demonstrates performance similar to high-field ion cyclotron resonance MS. High mass spectral characteristics
resulted in rapid acceptance of the Orbitrap FTMS for Life Sciences applications. The basics of Orbitrap operation are well
documented; however, like in any ion trap MS technology, its performance is limited by interactions between the ion clouds.
These interactions result in ion cloud couplings, systematic errors in measured masses, interference between ion clouds of
different size yet with close m/z ratios, etc. In this work, we have characterized the space-charge effect on the measured frequency for the Orbitrap FTMS,
looking for the possibility to achieve sub-ppm levels of mass measurement accuracy (MMA) for peptides in a wide range of total
ion population. As a result of this characterization, we proposed an m/z calibration law for the Orbitrap FTMS that accounts for the total ion population present in the trap during a data acquisition
event. Using this law, we were able to achieve a zero-space charge MMA limit of 80 ppb for the commercial Orbitrap FTMS system
and sub-ppm level of MMA over a wide range of total ion populations with the automatic gain control values varying from 10
to 107. 相似文献
22.
Fijalkowski KJ Genova RV Filinchuk Y Budzianowski A Derzsi M Jaroń T Leszczyński PJ Grochala W 《Dalton transactions (Cambridge, England : 2003)》2011,40(17):4407-4413
We describe the successful synthesis of the first mixed-cation (pseudoternary) amidoborane, Na[Li(NH(2)BH(3))(2)], with theoretical hydrogen capacity of 11.1 wt%. Na[Li(NH(2)BH(3))(2)] crystallizes triclinic (P1) with a = 5.0197(4) ?, b = 7.1203(7) ?, c = 8.9198(9) ?, α = 103.003(6)°, β = 102.200(5)°, γ = 103.575(5)°, and V = 289.98(5) ?(3) (Z = 2), as additionally confirmed by Density Functional Theory calculations. Its crystal structure is topologically different from those of its orthorhombic LiNH(2)BH(3) and NaNH(2)BH(3) constituents, with distinctly different coordination spheres of Li (3 N atoms and 1 hydride anion) and Na (6 hydride anions). Na[Li(NH(2)BH(3))(2)], which may be viewed as a product of a Lewis acid (LiNH(2)BH(3))/Lewis base (NaNH(2)BH(3)) reaction, is an important candidate for a novel lightweight hydrogen storage material. The title material decomposes at low temperature (with onset at 75 °C, 6.0% mass loss up to 110 °C, and an additional 3.0% up to 200 °C) while evolving hydrogen contaminated with ammonia. 相似文献
23.
Michal Reclo Erkan Yilmaz Yaroslav Bazel 《International journal of environmental analytical chemistry》2017,97(14-15):1315-1327
A switchable solvent-based micro-extraction method for pre-concentration and separation of ultratrace palladium was developed prior to its flame atomic absorption spectrometric detection. Reverse change of hydrophilicity of N,N-dimethylcyclohexylamine (DMA) was achieved by reaction with carbonated water. The hydrophilic bicarbonate salt of the protonated DMA was used as extractant for palladium complexed with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP). Formation of the hydrophobic form of switchable solvent from hydrophilic form of switchable solvent phase was achieved by addition of sodium hydroxide into the extractant-sample solution. The effect of key parameters affected extraction recovery was studied and optimised by using Plackett–Burman design, central composite design and three dimension (3D) surfaces response. The calibration plot was linear in the range 0.015–1.6 mg L?1 of palladium with a correlation coefficient of 0.999. The limit of detections values of palladium for liquid and solid samples were 4.28 μg L?1 and 0.54 µg g?1, respectively. The pre-concentration factor was 37.5. The accuracy was confirmed by determination of palladium in certified reference material. The procedure was also applied for determination of palladium content of real samples as automotive catalytic converter, roadside dust, sea water and river water. 相似文献
24.
Gerardo Algara‐Siller Dr. Nikolai Severin Samantha Y. Chong Dr. Torbjörn Björkman Dr. Robert G. Palgrave Andrea Laybourn Prof. Dr. Markus Antonietti Prof. Yaroslav Z. Khimyak Dr. Arkady V. Krasheninnikov Prof. Dr. Jürgen P. Rabe Prof. Dr. Ute Kaiser Prof. Andrew I. Cooper Prof. Dr. Arne Thomas Dr. Michael J. Bojdys 《Angewandte Chemie (International ed. in English)》2014,53(29)
25.
Andriy Romanyuk Viktor Melnik Yaroslav Olikh Johannes Biskupek Ute Kaiser Martin Feneberg Klaus Thonke Peter Oelhafen 《Journal of luminescence》2010,130(1):87-91
Silicon clusters embedded in a silicon dioxide matrix were prepared by ultrasound-assisted implantation resulting in a modified concentration of suboxide states as revealed by high-resolution photoelectron spectroscopy. It is suggested that ultrasound treatment results in formation of different interface structure between silicon cluster and silicon dioxide matrix which is characterized by a distinctly reduced concentration of the suboxide states. It is observed that photoluminescence properties are strongly correlated with the concentration of the suboxide states thereby providing an evidence that besides a quantum confinement effect a closer look at the chemical composition of the nc-Si/SiO2 system is important. 相似文献
26.
Perfluorinated benzocycloalkenes (benzocyclobutene, indan, tetralin), alkylbenzocycloalkenes and alkylbenzenes react with CF3COOH/SbF5 at 20-50 °C giving the corresponding carbonyl derivatives. 相似文献
27.
We study transport in ferromagnetic-superconductor/normal-metal systems. It is shown that charge and spin currents are pumped from ferromagnetic superconductors into adjacent normal metals by adiabatic changes in the order parameters induced by external electromagnetic fields. Spin and charge pumping identify the symmetry of the superconducting order parameter, e.g., singlet pairing or triplet pairing with opposite or equal spin pairing. Consequences for ferromagnetic-resonance experiments are discussed. 相似文献
28.
29.
Engineering the electromagnetic properties of periodic nanostructures using electrostatic resonances
Electromagnetic properties of periodic two-dimensional subwavelength structures consisting of closely packed inclusions of materials with negative dielectric permittivity epsilon in a dielectric host with positive epsilon(h) can be engineered using the concept of multiple electrostatic resonances. Fully electromagnetic solutions of Maxwell's equations reveal multiple wave propagation bands, with the wavelengths much longer than the nanostructure period. Some of these bands are described using the quasistatic theory of the effective dielectric permittivity epsilon(qs). Those bands exhibit multiple cutoffs and resonances which are found to be related to each other through a duality condition. An additional propagation band characterized by a negative magnetic permeability is found. Imaging with subwavelength resolution in that band is demonstrated. 相似文献
30.
Michael Anderson Atsushi Katsuda Yaroslav Kurylev Matti Lassas Michael Taylor 《Inventiones Mathematicae》2004,158(2):261-321
This paper explores and ties together three themes. The first is to establish regularity of a metric tensor, on a manifold with boundary, on which there are given Ricci curvature bounds, on the manifold and its boundary, and a Lipschitz bound on the mean curvature of the boundary. The second is to establish geometric convergence of a (sub)sequence of manifolds with boundary with such geometrical bounds and also an upper bound on the diameter and a lower bound on injectivity and boundary injectivity radius, making use of the first part. The third theme involves the uniqueness and conditional stability of an inverse problem proposed by Gelfand, making essential use of the results of the first two parts. 相似文献