INDEX mass spectrometry

Table 1.6 Substances identified by the electronic library (Wiley) in the Py-GC-MS analysis of Kraton 1107 with the eight most abundant masses and their relative intensities according to the Eight Peak Index (Mass Spectrometry Data Center) ...

Eow-density polyethylene - masterbatch Eow-density polyethylene - pro-oxidant Maleic anhydride Melt flow index Mass spectrometry Nuclear magnetic resonance Oxidative induction time Polyamide-6... 

When simple Hquids like naphtha are cracked, it may be possible to determine the feed components by gas chromatography combined with mass spectrometry (gc/ms) (30). However, when gas oil is cracked, complete analysis of the feed may not be possible. Therefore, some simple definitions are used to characterize the feed. When available, paraffins, olefins, naphthenes, and aromatics (PONA) content serves as a key property. When PONA is not available, the Bureau of Mines Correlation Index (BMCI) is used. Other properties like specific gravity, ASTM distillation, viscosity, refractive index. Conradson Carbon, and Bromine Number are also used to characterize the feed. In recent years even nuclear magnetic resonance spectroscopy has been... 

Eight Peak Index of Mass Spectra , Mass Spectrometry Data Center, AWRE, Aldermaston, Berkshire, Eng (1970) 44) K. Suryanarayanan... 

What is Mass Spectrometry - ASMS http //www.asms.org/whatisms/page-index.html... 

Camurri, G., Zaramella, A. High-throughput liquid chromatography/mass spectrometry method for the determination of the chromatographic hydrophobicity index. Anal. Chem. 2001,... 

DRI Differential refractive index EI-MS, El MS Electron impact mass spectrometry... 

GC-EAD Gas chromatography combined with an EAG detector GC-MS Gas chromatography combined with mass spectrometry HPLC High performance liquid chromatography KI Kovats retention index... 

IUPAC. Mass Spectrometry Terms and Definitions Project Page. 2007. Available at http // www.msterms.com/wiki/index.php title=Main Page. 

Five different detectors are common in HPLC (1) UV, (2) refractive index (RI), (3) conductivity, (4) inductively coupled plasma atomic emission, and (5) mass spectrometry. A UV detector passes a specific wavelength of UV light... 

Most compounds can be detected directly as they are able to produce a direct analytical signal. Photometric detection, especially UV (including diode array and multi-wavelength UV detection) is by far the most frequently applied detection technique. The application of mass spectrometry (MS) detection in CE is attractive as it can provide structural information [44]. Hologram-based refractive index detection [45] and electrochemical detection [46,47] were also reported. Conductivity [41,48-50] and amperometric [51,52] detection has shown to have advantages for the analysis of both organic and inorganic compounds. 

The development of mass spectroscopic techniques such as matrix assisted laser desorption (MALDI) and electrospray mass spectrometry has allowed the absolute determination of dendrimer perfection [7,8], For divergent dendrimers such as PAMAM and PPI, single flaws in the chemical structure can be measured as a function of generation to genealogically define an unreacted site of or a side reaction producing a loop at a particular generation level. Mass spectromet-ric results on dendrimers, not only demonstrate the extreme sensitivity of the technique, but also demonstrate the uniformity of the molecular mass. The polydispersity index of Mw/Mn for a G6 PAMAM dendrimer can be 1.0006 which is substantially narrower than that of living polymers of the same molecular mass [7],... 

As a result of advances in detection technology, newer HPLC detection techniques may be utilized. For example, evaporative light-scattering detection and refractive index detection may be used to quantify impurities with poor or no UV chromophore. Conductivity detection may also be used. In some cases, when no chromophore is present, chemical derivatization may be used to add a chromophore. Increasingly, tandem techniques such as liquid chromatography mass spectrometry (LC-MS) and GC-MS are utilized for impurity characterization. The highly selective nature of LC-MS ensures that few impurities are undetected. 

Although UV detection is most commonly used in the quahty control of drug substances, other detectors such as fluorescence, electrochemical, near infrared, refractive index, evaporative light scattering, or mass spectrometry may be used as appropriate. 

In the first step, we were able to separate this penta derivative by preparative H.P.L.C. and we subsequently treated it with an excess of propyleneimine in order to reach the required hexasubstituted compound. Under such conditions, we succeeded in preparing a N3P3(MeAz)g real sample (free of chlorine, as demonstrated by neutron activation analysis) identified by mass spectrometry (Fig. 32) and by P nmr (Fig. 33) (6 = — 36 ppm with 85 % HjPO as standard, to be compared with 8(N3P3Azg) = --37 ppm). The refractive index of this sample, n = 1.4825, appeared to be significantly far from Ratz s value. 

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