Spectrometer systems

Spectrometer systems for luminescence measurements are available from the major instrument companies, including Agilent, Horiba, PerkinElmer, Shimadzu, and Thermo Fisher Scientific. Only a few examples will be discussed the company websites provide information, applications, notes, and photos of their instrumentation. Luminescence spectrometers range from high-end research instruments to dedicated application instruments. 

For example, the Agilent Cary Eclipse spectrophotometer is a versatile instrument that allows fluorescence, phosphorescence, chemiluminescence, bioluminescence, and time-resolved phosphorescence measurements. It uses a xenon flash lamp, red-sensitive PMT, captures a data point every 

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Figure Bl.23.5. Schematic illustration of tlie TOE-SARS spectrometer system. A = ion gun, B = Wien filter, C = Einzel lens, D = pulsing plates, E = pulsing aperture, E = deflector plates, G = sample, PI = electron multiplier detector with energy prefilter grid and I = electrostatic deflector.

The term Q/TOF is used to describe a type of hybrid mass spectrometer system in which a quadrupole analyzer (Q) is used in conjunction with a time-of-flight analyzer (TOP). The use of two analyzers together (hybridized) provides distinct advantages that cannot be achieved by either analyzer individually. In the Q/TOF, the quadrupole is used in one of two modes to select the ions to be examined, and the TOF analyzer measures the actual mass spectrum. Hexapole assemblies are also used to help collimate the ion beams. The hybrid orthogonal Q/TOF instrument is illustrated in Figure 23.1. 

Once basic requirements and secondary objectives have been established, the prospective purchaser will find it easier to discuss details with sales representatives. From the latter s viewpoint, it is easier to talk to a potential customer who knows what he needs from a mass spectrometer system rather than to a customer who has only a vague idea of what is required. In fact, an uninformed customer can end up purchasing an expensive instrument that is far too good for the analyses required or, at the other extreme, a cheap instrument that is inadequate for immediate needs, let alone ones that might arise in the near future. 

Xps ndAes Instrumentation. The instmmentation required to perform xps and aes analyses is generally sophisticated and expensive (19). The need for UHV conditions in order to retain surface cleanliness for a tractable period of time was mentioned above. Beyond this requirement (and the hardware that accompanies it), the most important components of an electron spectrometer system are the source, the electron energy analyzer, and the electron detector. These will be discussed in turn below. 

In earlier procedures, the ReO anion was precipitated from water as the relatively insoluble potassium salt. Reduction of KReO with hydrogen gas gives rhenium metal, but the metal is contaminated with ca 0.4 wt % potassium that cannot be separated easily. Although suitable for some purposes, rhenium formed from KReO is found to be unsatisfactory in appHcations such as those for use in filaments in mass spectrometer systems. The route involving NH ReO avoids this problem. 

Ionization is brought about by Cl-hke processes and structural information is therefore limited unless a mass spectrometer system capable of MS-MS... 

FIG. 35. Vertical cross section of the reaction chamber equipped with the mass spectrometer system. Indicated are QMF. the quadmpole mass filter ESA. the electrostatic analyzer CD, the channeltron detector DE, the detector electronics DT, the drift tube lO, the ion optics TMP, the turbomolecular pump PR, the plasma reactor and MN. the matching network. 

In order to study the influence of ions on the deposition process, a reliable quantification of the ion flux and energy is imperative. This flux cannot be determined directly from the detected number of ions in an lED as measured by means of QMS, for three reasons [332]. First, the orifice size decreases during subsequent measurements due to deposition of a-Si H on the edges of the orifice. Second, due to the limited acceptance angle of the mass spectrometer system, only a fraction of the ions that arrive at the substrate is actually detected. This fraction depends on the type and number of interactions that an ion experiences while traversing... 

Electrospray Ionization - Mass Spectrometry (ESI-MS). The Jacobsen s Co-salen catalysts dissolved in dichloromethane were pumped to the mass spectrometer system after dilution with methanol at a flow rate of 50 pi min and 600 scans were collected in 1 min. 

Research users need full access to the functional elements of the spectrometer system and require the most efficient and flexible tools for MR sequence and application development. If the measurement methods delivered with the software do not adequately address the specific investigational requirements of a research team, modem NMR software is an open architecture for implementing new and more sophisticated functionality, with full direct access to all hardware controlling parameters. After evaluation, the new functionality can be developed with the help of toolbox functions that allow rapid prototyping and final builds, to enable the new sequence to be executed by non-experienced personnel and then used in routine applications. These toolboxes provide application oriented definitions and connect to standard mechanisms and routine interfaces, such as the geometry editor, configuration parameters or spectrometer adjustments. 

The Block II chemical biological mass spectrometer (CBMS II) is the most recent version in an evolution of fieldable mass spectrometer systems designed for military detection and identification of chemical and biological warfare agents (CWA and BWA, respectively). It builds on the experience and performance of previous versions and employs the latest advances in the components that comprise the system. Two of these predecessors in particular have made important contributions to this development, the mobile mass spectrometer (MM-1) and the Block I chemical biological mass spectrometer (CBMS I). 

Noda Y, Anzai K, Mori A, Kohno M, Shinmei M and Packer L. 1997. Hydroxyl, end superoxide anion radical scavenging activities of natural source antioxidants using the computerized JES-FR30 ESR spectrometer system. Biochem Mol Biol Int 42(1) 35—44. 

Any spectrometer system capable of doing complicated two-dimensional NMR work will have a sufficient data system and pulse programmer. The... 

It has been hoped [20,21] that a method could be developed which would directly detect the radioatoms that are present in nature by an efficient ultra-sensitive mass spectrometer technique which would not itself depend upon the fact that the atoms being investigated are radioactive. The advantage of an efficient mass spectrometer system for long-lived radioisotopes can be seen from the equation for calculating the number of atoms present in a sample from its measured radioactive decay rate ... 

Fowler-Nordheim tunneling of, 22 258 in HBTs, 22 167-168 Moore s law and device scaling and, 22 254 in RTDs, 22 170-171 in semiconducting silicon, 22 485-486 in semiconductors, 22 233, 237-239 in SETs, 22 171-172 in single layer OLEDs, 22 215-216 in spinel ferrites, 11 60-61 in the superconducting state, 23 804 Electron spectrometer system, components of, 24 100-101... 

Fig. 19.14. Accumulation of phosphate salts in the atmospheric pressure ionization chamber. Note the large accumulation of salts on the striker plate. Additional accumulation of salts can be seen on the back walls of the chamber. The general dustiness in the chamber is salt accumulation. This source is a z-spray ionization source chamber of a Micromass Quattro Ultima mass spectrometer system.

NMR imaging spectrometer systems, Vis, 1120 Auburn Road, Fremont, California 94538, USA... 

Artifacts may be roughly categorized into those due to inherent limitations (e.g. pulses cannot excite unlimited bandwidths even if all hardware components work perfectly) and those that result from improper set-up of the experiment or nonideal functioning of the NMR spectrometer system. In this chapter we will mainly focus on the latter two. These artifacts are more likely to appear in multiple-pulse experiments. Quite often, they are avoided by clever programming of the experiments (e.g. interleaved acquisition of data for NOE spectra, use of pulsed-field gradients instead of phase-cycling). 

Figure 3.20 Diagrammatic representation of a quadrupole mass spectrometer system.

Recently, a new on-line mass spectrometer system was introduced to the Ernest B. Yeager Center for Electrochemical Sdences and was used for various aspects of electrochemical studies. In this thesis, the online mass spectrometer was used to analyze the products of methanol oxidation. 

J.E. Parmeter, G.A. Eiceman andJ.E. Rodriguez, Trace Detection of Narcotics Using a Preconcentrator/ Ion Mobility Spectrometer System, NIJ Report 602-00, April 2001. 

K.B. Pfeifer and R.C. Sanchez, Miniaturized ion mobility spectrometer system for explosives and contraband detection. International Journal for Ion Mobility Spectrometry 5(3) (2002) 63—66. 

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