scholarly journals Secondary Ion Yield and Fragmentation of Biological Molecules by Employing 35Cl Primary Ions within the MeV Energy Domain

2019 ◽  
Vol 31 (1) ◽  
pp. 117-123 ◽  
Author(s):  
Boštjan Jenčič ◽  
Primož Vavpetič ◽  
Mitja Kelemen ◽  
Primož Pelicon
Keyword(s):  
Biological Molecules ◽  
Energy Domain ◽  
Primary Ions ◽  
Secondary Ion

Ion yield improvement for static secondary ion mass spectrometry by use of polyatomic primary ions

2008 ◽  
Vol 22 (10) ◽  
pp. 1481-1496 ◽  
Author(s):  
Roel De Mondt ◽  
Luc Van Vaeck ◽  
Andreas Heile ◽  
Heinrich F. Arlinghaus ◽  
Nicolas Nieuwjaer ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Yield Improvement ◽  
Ion Mass Spectrometry ◽  
Primary Ions ◽  
Secondary Ion

scholarly journals Dust Experiment for a Rendezvous Cometary Mission

1980 ◽  
Vol 90 ◽  
pp. 273-273
Author(s):  
B.-K. Dalmann ◽  
D. Bahr ◽  
H. Fechtig ◽  
J. Kissel
Keyword(s):  
Mass Range ◽  
Mass Region ◽  
Dust Particles ◽  
Simulation Studies ◽  
Quadrupole Mass ◽  
Mass Filter ◽  
Oxygen Ions ◽  
Secondary Ions ◽  
Primary Ions ◽  
Secondary Ion

During a Rendezvous-type cometary mission it will be possible to collect dust particles on exposed surfaces. A secondary-ion-mass-spectrometer is proposed for the subsequent chemical investigation of such dust collections. An ion gun shoots inert gas or oxygen-ions onto the sample. The energy of these primary ions can be chosen between 1 and 5 keV. The positive and negative secondary ions emitted from the dust surfaces are then analysed with a quadrupole mass filter. The mass range of the instrument will be 1-150 amu. The sensor is able to measure (a) nearly all elements in this mass region, (b) molecules and organic components present in the dust, (c) isotopic ratios of interesting elements. Results of a first series of simulation studies are reported.

Laser Desorption/Ablation Plumes from Capillary-Like Restricted Volumes

2009 ◽  
Vol 15 (2) ◽  
pp. 189-198 ◽  
Author(s):  
Richard Knochenmuss
Keyword(s):  
Laser Desorption ◽  
Laser Desorption Ionization ◽  
Free Jets ◽  
Structured Surfaces ◽  
Desorption Ionization ◽  
Ion Molecule Reactions ◽  
Secondary Reactions ◽  
Ionization Model ◽  
Primary Ions ◽  
Secondary Ion

Laser desorption/ionization from structured surfaces has been the object of recently renewed interest. Conditions in the plume of material ablated from such surfaces may differ from those of a sample which is ablated in bulk. Since recombination and secondary ion–molecule reactions in the plume play a major role in determining the types and quantities of ions observed at the detector, these differences are analytically relevant. Desorption/ionization substrates with channels of high aspect ratio are modeled as capillary nozzles, from which free jets are emitted. A previously developed matrix-assisted laser desorption/ionization ablation/ionization model is adapted for these jets. More primary ions reach the detector when ablated from a capillary orifice, but fewer analye ions are created in secondary reactions. These differences in ion yield can persist for arrays of capillaries on the surface, depending on the ratio of their diameter to spacing.

Molecular surface analysis by TOF-SIMS

1992 ◽  
Vol 50 (2) ◽  
pp. 1556-1557
Author(s):  
Robert W. Odom
Keyword(s):  
Mass Spectrometry ◽  
Surface Analysis ◽  
Secondary Ion Mass Spectrometry ◽  
Molecular Ions ◽  
Molecular Surface ◽  
Tof Sims ◽  
Ion Mass Spectrometry ◽  
Static Conditions ◽  
Primary Ions ◽  
Secondary Ion

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) performs surface sensitive analysis of the elemental and molecular composition of solids. TOFSIMS is a relatively new embodiment of static secondary ion mass spectrometry (SSIMS) in which the dose of primary ions incident on the surface is typically less than 1012 ions/cm2. Since typical solid surfaces have an atomic density of 1015 atoms/cm2, this primary ion dose nominally removes less than 0.1% of a monolayer. Hence, SIMS analyses performed under these static conditions represent near surface analysis in which secondary ions are produced from the top few monolayers of the surface. The actual sampling depth is determined by the primary ion momentum, angle of incidence and chemistry of the surface. Since low dose primary ions cause minimal perturbation of the chemistry of the solid surface, SSIMS analyses often produce molecular or pseudo-molecular ions characteristic of the chemical composition of the surface. Thus, molecular ions or structurally significant fragment ions are often observed in SSIMS analyses of surfaces containing inorganic and organic residues, polymers surfaces, coatings, and biological materials such as tissues and membranes.

Secondary ion mass spectrometry of sodium nitrate: comparison of ReO4− and Cs+ primary ions

1997 ◽  
Vol 163 (3) ◽  
pp. 185-195 ◽  
Author(s):  
G.S. Groenewold ◽  
J.E. Delmore ◽  
J.E. Olson ◽  
A.D. Appelhans ◽  
J.C. Ingram ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Sodium Nitrate ◽  
Secondary Ion Mass Spectrometry ◽  
Ion Mass Spectrometry ◽  
Primary Ions ◽  
Secondary Ion

Effects of Sputtered Particle Energy on the Properties of SiO2 Films

1988 ◽  
Vol 128 ◽  
Author(s):  
Yasunori Taga ◽  
Takeshi Ohwaki
Keyword(s):  
Particle Energy ◽  
Cluster Ions ◽  
Energy Distributions ◽  
Ion Energy ◽  
Current Voltage ◽  
Current Voltage Characteristics ◽  
Ion Energy Distributions ◽  
Primary Ions ◽  
Secondary Ion ◽  
Silicon Oxygen

ABSTRACTThe secondary ion energy distributions (SIED) emitted from Si under various conditions of targets (Si, SiO2) and primary ions (Ar+, O+) were measured and the thin SiO2 films were deposited by magnetron sputtering techniques under the corresponding conditions to the SIED experiments. The most probable energies of silicon oxygen cluster ions of SimOn+ (m, n=l, 2,…) are equal to those of Al+ thermal ions, while those of Siℓ+ (ℓ=l, 2,…) remain unchanged with the introduction of oxygen in chamber during Ar+ ion bombardment. The currentvoltage plots of SiO2 films are also measured and found to be influenced by the deposition conditions.It is concluded that the differences in current-voltage characteristics of SiO2 films prepared under various sputtering conditions can be reasonably explained in terms of the changes in the most probable energy of the sputtered particles.

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