Mass spectrometer polymer membrane sample introduction device

1983 ◽  
Vol 55 (4) ◽  
pp. 813-814 ◽  
Author(s):  
George J. Kallos ◽  
Nels H. Mahle
Keyword(s):  
Mass Spectrometer ◽  
Polymer Membrane ◽  
Sample Introduction ◽  
Membrane Sample

New sample introduction technique for mass spectrometer

1970 ◽  
Vol 42 (8) ◽  
pp. 950-952 ◽  
Author(s):  
Frank G. Padrta ◽  
J. J. Donohue
Keyword(s):  
Mass Spectrometer ◽  
Sample Introduction

Six-Dimensional Automatic Sample Introduction System for Mass Spectrometer

2013 ◽  
Vol 427-429 ◽  
pp. 1113-1116
Author(s):  
Dong Zhang ◽  
Zhi Quan Zhou ◽  
Zhan Feng Zhao
Keyword(s):  
Mass Spectrometer ◽  
Ion Source ◽  
Sample Introduction ◽  
Stepper Motor ◽  
Main Function ◽  
Dimensional Control ◽  
Sample Introduction System ◽  
Improving Accuracy

In a mass spectrometer, the main function of the sample introduction system is to inject the sample, whose accuracy and reliability affect the efficiency of ionizing directly, and then influence the results. Considering this, the six-dimensional control platform based on stepper motor is proposed, improving accuracy of DAPCI ion source greatly.

scholarly journals Organic and inorganic decomposition products from the thermal desorption of atmospheric particles

2015 ◽  
Vol 8 (12) ◽  
pp. 13377-13421 ◽  
Author(s):  
B. J. Williams ◽  
Y. Zhang ◽  
X. Zuo ◽  
R. E. Martinez ◽  
M. J. Walker ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Mass Spectrometer ◽  
Thermal Desorption ◽  
Sample Introduction ◽  
Organic Nitrate ◽  
Aerosol Composition ◽  
Decomposition Products ◽  
Aerosol Mass ◽  
Thermal Decomposition Products ◽  
Mass Concentrations

Abstract. Atmospheric aerosol composition is often analyzed using thermal desorption techniques to evaporate samples and deliver organic or inorganic molecules to various designs of detectors for identification and quantification. The organic aerosol (OA) fraction is composed of thousands of individual compounds, some with nitrogen- and sulfur-containing functionality, and often contains oligomeric material, much of which may be susceptible to decomposition upon heating. Here we analyze thermal decomposition products as measured by a thermal desorption aerosol gas chromatograph (TAG) capable of separating thermal decomposition products from thermally stable molecules. The TAG impacts particles onto a collection and thermal desorption (CTD) cell, and upon completion of sample collection, heats and transfers the sample in a helium flow up to 310 °C. Desorbed molecules are refocused at the head of a GC column that is held at 45 °C and any volatile decomposition products pass directly through the column and into an electron impact quadrupole mass spectrometer (MS). Analysis of the sample introduction (thermal decomposition) period reveals contributions of NO+ (m/z 30), NO2+ (m/z 46), SO+ (m/z 48), and SO2+ (m/z 64), derived from either inorganic or organic particle-phase nitrate and sulfate. CO2+ (m/z 44) makes up a major component of the decomposition signal, along with smaller contributions from other organic components that vary with the type of aerosol contributing to the signal (e.g., m/z 53, 82 observed here for isoprene-derived secondary OA). All of these ions are important for ambient aerosol analyzed with the aerosol mass spectrometer (AMS), suggesting similarity of the thermal desorption processes in both instruments. Ambient observations of these decomposition products compared to organic, nitrate, and sulfate mass concentrations measured by an AMS reveal good correlation, with improved correlations for OA when compared to the AMS oxygenated OA (OOA) component. TAG signal found in the traditional compound elution time period reveals higher correlations with AMS hydrocarbon-like OA (HOA) combined with the fraction of OOA that is less oxygenated. Potential to quantify nitrate and sulfate aerosol mass concentrations using the TAG system is explored through analysis of ammonium sulfate and ammonium nitrate standards. While chemical standards display a linear response in the TAG system, re-desorptions of the CTD cell following ambient sample analysis shows some signal carryover on sulfate and organics, and new desorption methods should be developed to improve throughput. Future standards should be composed of complex organic/inorganic mixtures, similar to what is found in the atmosphere, and perhaps will more accurately account for any aerosol mixture effects on compositional quantification.

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