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1.
T. Rietmann S. Sohn M. Schröder D. Lipinsky H.F. Arlinghaus 《Applied Surface Science》2006,252(19):6640-6643
In order to improve quantification of high mass ions, the influence of cluster composition on detection efficiencies has been studied using a TOF-SIMS IV with the extended capability of postaccelerating ions up to 20 keV. In this experimental study, we focus on the comparison of detection efficiencies for three types of negatively charged secondary cluster ions: gold-alkanethiolate-clusters (AuxMy), gold-sulfur-clusters (AuxSy) and gold-clusters (Aux). The clusters were sputtered from self-assembled monolayers of hexadecanethiols on gold substrates using 10 keV Ar+ primary ions. The detection efficiencies were derived on the basis of a function for the secondary electron yield and a fourth-order approximated Poisson probability distribution for electron propagation and amplification within the microchannel plate.In addition to the well-known dependence of detection efficiencies on ion mass and energy, which has already been studied for positively charged ions, we were able to show a similar behaviour for the investigated negatively charged secondary ions. We have observed major variations among the three types of clusters at similar mass and energy as predicted in a theoretical approach. The observed differences are due to the different composition of the investigated clusters which has a major influence on the kinetic ion induced electron emission within the microchannel plate. For the first time it was possible to experimentally verify these predictions for detection efficiencies. 相似文献
2.
Oriňák Andrej Arlinghaus Heinrich Frank Vering Guido Justinová Martina Oriňáková Renáta Turčániová L’udmila Halama Maroš 《平面色谱法杂志一现代薄层色谱法》2003,16(1):23-27
JPC – Journal of Planar Chromatography – Modern TLC - Two interfaces have been tested for coupling thin-layer chromatography (TLC) with time-of-flight secondary-ion mass spectrometry... 相似文献
3.
Oriňák Andrej Vering Guido Arlinghaus Heinrich F. Andersson Jan T. Halas Ladislav Oriňáková Renáta Turčániová Ľudmila 《平面色谱法杂志一现代薄层色谱法》2005,18(1):44-50
JPC – Journal of Planar Chromatography – Modern TLC - A new hyphenated technique that enables coupling of thin-layer chromatography (TLC) with time-of-flight secondary-ion mass... 相似文献
4.
D. Thao Nguyen Matthias Freitag Christian Gutheil Dr. Kai Sotthewes Dr. Bonnie J. Tyler Dr. Marcus Böckmann Mowpriya Das Friederike Schlüter Prof. Dr. Nikos L. Doltsinis Prof. Dr. Heinrich F. Arlinghaus Prof. Dr. Bart Jan Ravoo Prof. Dr. Frank Glorius 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13754-13759
5.
D. Thao Nguyen Matthias Freitag Christian Gutheil Kai Sotthewes Bonnie J. Tyler Marcus Bckmann Mowpriya Das Friederike Schlüter Nikos L. Doltsinis Heinrich F. Arlinghaus Bart Jan Ravoo Frank Glorius 《Angewandte Chemie (International ed. in English)》2020,59(32):13651-13656
A novel photoresponsive and fully conjugated N‐heterocyclic carbene (NHC) has been synthesized that combines the excellent photophysical properties of arylazopyrazoles (AAPs) with an NHC that acts as a robust surface anchor (AAP‐BIMe). The formation of self‐assembled monolayers (SAMs) on gold was proven by ToF‐SIMS and XPS, and the organic film displayed a very high stability at elevated temperatures. This stability was also reflected in a high desorption energy, which was determined by temperature‐programmed SIMS measurements. E‐/Z‐AAP‐BIMe@Au photoisomerization resulted in reversible alterations of the surface energy (i.e. wettability), the surface potential (i.e. work function), and the conductance (i.e. resistance). The effects could be explained by the difference in the dipole moment of the isomers. Furthermore, sequential application of a dummy ligand by microcontact printing and subsequent backfilling with AAP‐BIMe allowed its patterning on gold. To the best of our knowledge, this is the first example of a photoswitchable NHC on a gold surface. These properties of AAP‐BIMe@Au illustrate its suitability as a molecular switch for electronic devices. 相似文献
6.
F.J. Arlinghaus 《Journal of Physics and Chemistry of Solids》1974,35(8):931-935
The energy band structure of stannic oxide has been calculated by a self-consistent augmented plane wave (APW) method. The calculation predicts SnO2 to be a semiconductor with an allowed direct band gap of 3·68 eV for light polarized perpendicular to the tetragonal axis, and of 4·07 eV for parallel polarized light; these values agree well with the measured values of 3·57 and 3·93 eV. The theory also predicts indirect and direct-forbidden optical transitions which are consistent with experiment. 相似文献
7.
C. Kriegeskotte T. Cantz J. Haberland A. Zibert J. Haier G. Köhler H. R. Schöler H. H.‐J. Schmidt H. F. Arlinghaus 《Journal of mass spectrometry : JMS》2009,44(10):1417-1422
Disease progression and clinical diagnostics of a number of hereditable metabolic diseases are determined by organ involvement in disturbed deposition of certain molecules. Current clinical imaging is unable to visualize this maldistribution with sufficient specificity and sensitivity, such as in Wilson's disease. The quest for understanding cellular Cu distribution in these patients requires element‐ and molecule‐specific images with nanometer‐scale spatial resolution. We have used a new cryo‐mass spectrometric instrument with an integrated cryosectioning chamber for preparation and analysis of frozen hydrated samples of Wilson's disease tissue. With laser post‐ionization secondary neutral mass spectrometry (laser‐SNMS), we were able to image Cu and other intrinsic elements and molecules in less than 1 mg of frozen hydrated liver tissue from a murine model of Wilson's disease. A 40–50 times higher Cu concentration was measured in the disease tissue as compared to the control mouse. Furthermore, major histomorphological changes were observed using this advanced nano‐science tool. The results showed that the combination of in‐vacuum cryosectioning and cryo‐laser‐SNMS technologies is particularly well suited for identifying specific cell structures and imaging trace element concentrations with subcellular resolution and upper‐parts‐per‐billion sensitivity in biological samples. This technology can provide a novel diagnostic tool for clinical applications in various diseases involving trace elements. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
8.
Roel De Mondt Luc Van Vaeck Andreas Heile Heinrich F. Arlinghaus Frank Vangaever Jens Lenaerts 《Analytical and bioanalytical chemistry》2009,393(8):1917-1921
Recent publications on static secondary ion mass spectrometry (S-SIMS) focus on molecular depth profiling by using polyatomic
or ultra-low energy monoatomic projectiles. Since their applicability depends on the relationship between the ion yield and
the depth, which is hard to obtain without extensive studies, a combination of a wear test method with S-SIMS surface analysis
was performed in the current study. Using this non-sputtering procedure, the relation between the signal intensity and the
local concentration remains in principle the same as that at the surface (which is easy to determine). Mechanical erosion
was successfully applied to expose sub-surface material from organic multilayers. Through surface analysis with S-SIMS on
the gradually exposed deeper planes, molecular depth profiles could be obtained. The study was conducted on a model system
relevant to offset printing, consisting of two polymer layers, containing dyes and a surfactant, cast on an Al substrate.
Figure Concept of mechanical erosion followed by S-SIMS surface analysis to obtain molecular depth profiles 相似文献
9.
Martin Körsgen Andreas Pelster Klaus Dreisewerd Heinrich F. Arlinghaus 《Journal of the American Society for Mass Spectrometry》2016,27(2):277-284
The analytical sensitivity in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is largely affected by the specific analyte-matrix interaction, in particular by the possible incorporation of the analytes into crystalline MALDI matrices. Here we used time-of-flight secondary ion mass spectrometry (ToF-SIMS) to visualize the incorporation of three peptides with different hydrophobicities, bradykinin, Substance P, and vasopressin, into two classic MALDI matrices, 2,5-dihydroxybenzoic acid (DHB) and α-cyano-4-hydroxycinnamic acid (HCCA). For depth profiling, an Ar cluster ion beam was used to gradually sputter through the matrix crystals without causing significant degradation of matrix or biomolecules. A pulsed Bi3 ion cluster beam was used to image the lateral analyte distribution in the center of the sputter crater. Using this dual beam technique, the 3D distribution of the analytes and spatial segregation effects within the matrix crystals were imaged with sub-μm resolution. The technique could in the future enable matrix-enhanced (ME)-ToF-SIMS imaging of peptides in tissue slices at ultra-high resolution. 相似文献
10.
Wendeln C Rinnen S Schulz C Kaufmann T Arlinghaus HF Ravoo BJ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(19):5880-5888
Microcontact chemistry has been applied to patterned glass and silicon substrates by successive reaction of unprotected and monoprotected heterobifunctional linkers with alkene-terminated self-assembled monolayers (SAMs) to produce bi-, tri-, and tetrafunctional surfaces. Photochemical microcontact printing of an azide thiol linker followed by immobilization of an acid thiol linker on an undecenyl-terminated SAM results in a well-defined, micropatterned surface with terminal azide, acid, and alkene groups. Biologically relevant molecules (biotin, carbohydrates) have been selectively attached to the surface by means of orthogonal ligation chemistry, and the resulting microarrays display selective binding to fluorescently labeled proteins. An orthogonally addressable, tetrafunctional surface (azide, acid, alkene, and amine) can be prepared by an additional printing step of a tert-butyloxycarbonyl (Boc)-protected alkyne amine linker on the azide structures by using the copper(I)-catalyzed azide-alkyne Huisgen cycloaddition and subsequent removal of the protective group. 相似文献