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We describe the design and operating characteristics of a simple polarized atomic hydrogen beam particularly suitable for applications to crossed beams experiments. In addition to experimental measurements, we present the results of detailed computer models, using Monte-Carlo ray tracing techniques, optical analogs, and phase-space methods, that not only provide us with a confirmation of our measurement, but also allow us to characterize the density, polarization, and atomic fraction of the beam at all points along its path. As a subsidiary result, we also present measurements of the relative and absolute efficiencies of the V/G Supavac mass analyzer for masses 1 and 2.

Samples of SAP, 9.4 wt % Al 2 O 3 , were irradiated at temperatures between 350C and 500C with He + and then H 2 + ions to gas concentrations of about 1000 appm each. During the irradiation, the samples were continuously oscillated through an arc so as to spread out the end-of-range region and produce a uniform gas concentration in a section of the specimen about 3 μm thick. Following irradiation, foils extracted from the irradiated volume were examined by TEM and cavities were observed in all samples. Cavity size and number density varied with irradiation temperature. Calculations indicate that all of the helium can be accommodated in the cavities. Hydrogen analysis, with an Ion Microprobe Mass Analyzer, showed no accumulation of hydrogen in the cavities or elsewhere in samples irradiated at 400C and 500C.

For the purpose of identification of “plate-out” matters from polyvinylchloride compound by using laser microprobe mass analyzer (LAMMA), a quartz wool sampling technique was invented for a trace amount of “plate-out” matters from a roller. Particulate matters attached to the quartz wool by scratching off from “plate-out” matters on the roller were investigated. Among di-octylphthalate, calcium stearate, zinc stearate, di-buthyl-tin-maleate and ST-210 in the compound, it was found that calcium stearate adhered preferentially on the roller from the compound.

The application of lasers in mass-spectrometric investigations is reported. Attention is focused on the description of a commercial laser microprobe mass analyzer (LAMMA) made by Leybold-Heraeus and on some features of the application of the technique to the study of biological specimens. Methods of preparing biological specimens for analysis are described and approaches to the quantitative and qualitative explanation of the spectra are presented. Characteristic features of LAMMA spectra of biological and biomedical specimens are described. Future prospects for various applications of the LAMMA technique are assessed.

A combined field ionization-collision-induced dissociation instrument has been constructed that will allow the determination of structure of individual components in a complex mixture. A high transmission mass analyzer, differentially pumped collision cell and a spherical electrostatic analyzer are employed to allow collisional spectra to be recorded using samples containing approximately 1 μg per component.

I have tried to explain that each of the mass analyzers discussed has specific merits and limitations. The picture present in your mind depends on the side from which you look (Fig. 178) as is true to mass spectrometry. Positive and negative features are always combined in one instrument as Dr. Jekyll and Mr. Hyde are combined in one person. By the way, R.L. Stevenson (Fig. 179), one of the famous authors mentioned who lived a few miles from here in Monterey (Fig. 180), published the fascinating Jekyll and Hyde story 100 years ago, in 1886. Figure 181 again presents all of the instrument bar graphs together. They can be interpreted as spectra characterizing each analyzer. I have asked M.C. ten Noever de Brauw to apply the Arthur pattern recognition/non-linear mapping program [312], which is used, for example to classify pyrolysis mass spectra [313], and to convert these graphs accordingly. Figure 182 shows the results. The systems forms islands (you might find out which one could be considered Stevenson's “Treasure Island”). Traffic goes back and forth between the islands as shown in Fig. 183. Conferences like Asilomar are to keep the traffic going. The islands are all different, none of them is perfect, and development work is continuing. There is no final solution. However, I think we should not be bothered by this fact. On the contrary, so-called perfect solutions pretending completion very often result in later disappointment. The old philosophers knew that hundreds of years ago. In conclusion, let me close with one line from Lao Tzu's Tao Te Ching (Fig. 184). The translation of the Chinese text reads. “If the greatest achievement is incomplete, then its usefulness is unimpaired.”

Two techniques are applied to ion collision studies. The first, Aston banding, is native to mass spectrometry, and effectively makes of a simple mass analyzer a double mass spectrometer which separates unambiguously the parent ions from the products. By combining with the mass spectrometer a "high-pass" energy filter, we are able to study ionic collisions which take place in the drift regions both before and after the magnetic analyzer. We describe the methods whereby we measure total cross sections for both charge exchange and collision-induced dissociation and show how we measure the loss and distribution of energy and momentum of the high-velocity product ions. The accelerating potential range for our ion collisions is 0.6 to 2.0 kv.The second technique, the detailed comparison of appearance potential curves, complements Aston banding although it has broader application. We describe how, from the ratio of the A.P. curve of the product to that of the parent, one can determine directly the influence of metastable or long-lived excited ions in the parent ion beam. We further describe how, from the ratio of the differences of slopes, one can determine the relative and sometimes the absolute cross sections associated with these states of the ion which enter into collision with a particular ion kinetic energy. In this paper, the techniques and the conditions under which they are applicable are stressed. In subsequent papers, we shall discuss results obtained with the techniques involving ions coming from Ar, H2, N2, and O2.

107 compounds have been qualitatively identified in the water of the Segara Anakan Nature Reserve, Indonesia, using liquid chromatography - mass spectrometry (LC-MS), and specially, using time-of-flight (TOF) mass analyzer. Ten stations represented both anthropogenic (oil refinery site) types and natural (riverine, lagoon, marine) were considered. Dimecrotic acid, hymechromone, valeryl salycilate, and phthalic acid mono-2-ethylhexyl ester were discovered at all station indicating apportionment from certain administered medications and from using ubiquitous plastic.

Although available commercially since the mid-1950s, there has been a renewed and increasing interest in time-of-flight mass spectrometers during the last decade or more. Improvements have been made in mass resolution; and high-speed data acquisition systems have been developed which enable the recording of all ions in each time-of-flight cycle. Most importantly, these instruments have been coupled with several new ionization techniques, which are capable of desorbing the relatively large and intractable biopolymers whose structures are of interest to molecular biologists, biochemists and biophysicists. Primarily these are techniques which employ pulsed lasers, fission fragments and pulsed ion beams, for which a ‘non-scanning’ and/or high-transmission analyzer provides considerable analytical advantage. In this report we review some basic principles of the time-of-flight mass analyzer, highlighting efforts to improve dynamic focusing for instruments forming ions in the gas phase and static focusing for desorption instruments, and the progression from time-slice to time-array detection. We also review some of the accomplishments of instruments employing the time-of-flight analyzer, including: molecular weight determinations for peptides and small proteins; the analysis of tryptic digests, crude extracts and whole cells; the structural analysis of glycolipids, phospholipids and lipopolysaccharides; and the determination of covalent and metal-linked peptide dimers. We conclude with some recent developments in combining the time-of-flight analyzer with liquid chromatography using the continuous flow probe technique.

A new sample chamber has been developed for LAMMA enabling micro area analysis of large samples. The ionizing pulse laser is ultimately focused onto a selected sample area from the same side from which the ions are extracted for mass analysis. Details on the construction of the chamber will be given.

Many reports have been published for the automatic control of SIMS instruments, but most of them are based on rather expensive systems. The present paper describes a more economical system for an Applied Research Laboratories’ Ion Microprobe Mass Analyzer.

The 12 month period from May 1988 to July 1989 represents the first full year of our 18 month pilot program in nuclear structure research. In this period, research was initiated to develop a capability for radioactive secondary beams at Argonne National Laboratory using the Atlas and the new Fragment Mass Analyzer (FMA), which is currently under construction. Two major new detector facilities are currently in the final stages of design and testing. The Large-Area, Scintillator Telescope (LAST) detector is fully operational and will be shipped to Argonne National Laboratory in August for fit-tests and in-beam calibrations. The first segments of a new sixteen-segment neutron multiplicity detector have been built and tested. The remaining segments are currently being constructed. Research was continued in the areas of (1) Coulomb excitation studies of rare earth and actinide nuclei; (2) In-beam, gamma-ray spectroscopy of nuclei in the mass 100 region, and (3) Advanced detector design. Several journal articles and abstracts were published or submitted for publication in the reporting period, and others are currently in preparation. Three graduate students participated in the program, one from the University of Florida and two from the Royal Institute of Technology, Stockholm, Sweden.

On the metal surface bombarded by incident ions, there is recognized the irregular pattern by TSUNOYAMA (1), that is called a cone. The cone affects inexplicably on the precision of ion mass spectrometry. However, the mechanism of cone growth is not well revealed. To clarify this, the experiment using 42%Ni-Fe alloy has been carried out in the ion mass analyzer.

The operation and development of ATLAS are reported, including accelerator improvements. Particularly noted is an upgrade to extend the mass range of projectiles up to uranium and to increase the beam intensity by at least two orders of magnitude for all ions. Meetings are discussed, particularly of the Program Advisory Committee and the User Group Executive Committee. Some basic information is provided for users planning to run experiments at ATLAS, including a table of beams available. The data acquisition system for ATLAS, DAPHNE, is discussed, as are the following experimental facilities: the Argonne-Notre Dame Gamma Ray Facility, a proposal submitted for constructing a large-acceptance Fragment Mass Analyzer. Brief summaries are provided of some recent experiments for which data analysis is complete. Experiments performed during the period from June 1, 1986 to January 31, 1987 are tabulated, providing the experiment number, scientists, institution, experiment name, number of days, beam, and energy. (LEW)

The 12 month period from May 1988 to July 1989 represents the first full year of our 18 month pilot program in nuclear structure research. In this period, research was initiated to develop a capability for radioactive secondary beams at Argonne National Laboratory using the Atlas and the new Fragment Mass Analyzer (FMA), which is currently under construction. Two major new detector facilities are currently in the final stages of design and testing. The Large-Area, Scintillator Telescope (LAST) detector is fully operational and will be shipped to Argonne National Laboratory in August for fit-tests and in-beam calibrations. The first segments of a new sixteen-segment neutron multiplicity detector have been built and tested. The remaining segments are currently being constructed. Research was continued in the areas of (1) Coulomb excitation studies of rare earth and actinide nuclei; (2) In-beam, gamma-ray spectroscopy of nuclei in the mass 100 region, and (3) Advanced detector design. Several journal articles and abstracts were published or submitted for publication in the reporting period, and others are currently in preparation. Three graduate students participated in the program, one from the University of Florida and two from the Royal Institute of Technology, Stockholm, Sweden.

A computer was interfaced to an ion microprobe mass analyzer for more rapid data acquisition and analysis. The interface is designed to allow data acquisition, independent of the computer. A large data analysis package was developed and implemented. Performance of the computerized system was evaluated and compared to manual operation.

The use of a cesium source [1] in an ion microprobe mass analyzer (ARL-IMMA) has led to the development of characteristic topography inside and outside sputtered areas in GaAs.

The erythrocyte magnesium content was determined using two different analytical systems (atomic absorption spectrometry and the laser microprobe mass analyzer) with specimens from 18 patients with normal renal function and from 10 patients with chronic renal insufficiency. There was a good correlation (r = 0.73) between the two analytical systems. Additionally, the laser microprobe mass analyzer was used to determine the aluminum content of plasma and erythrocytes in specimens from patients who ingested moderate quantities of aluminum hydroxide for several months. Results showed a significant elevation of the plasma aluminum concentration, but a normal erythrocyte aluminum content. The laser microprobe mass analyzer may be useful in studies of mineral metabolism in humans.

A technique involving a new substage assembly was developed to permit an ion microprobe mass analyzer (IMMA) to be used as an ion bombardment facility for molten metals (lithium) without harm to the instrument from the hot, reactive samples.

A vacuum sample holder designed to protect moisture‐sensitive or air‐sensitive materials from exposure prior to examination in the ion microprobe is described. The advantage of this piece of apparatus is that samples can be loaded in inert atmospheres and transported in vacuum to the ion microprobe for analysis without exposure to moisture or air.

Lithium clusters containing up to 15 atoms were prepared by evaporation in an inert gas at a pressure of 10 -4 ∼10 -3 Torr and the mass numbers of these clusters were measured by a mass analyzer. The following are the main results. i) In good vacuum lithium was detected as single atoms. ii) When an inert gas was present, Li 2 , Li 4 , Li 6 and Li 8 were always detected; however, Li 3 and Li 5 were never detected. Li 7 and Li 9 were detected in smaller amounts than those of neighbouring clusters. iii) In the range Li 10 to Li 15 all possible clusters were detected and Li 13 was most abundant among them.