| dc.contributor.author | Sun, Xunyun. | en_US |
| dc.date.accessioned | 2014-10-21T12:37:00Z | |
| dc.date.available | 1993 | |
| dc.date.issued | 1993 | en_US |
| dc.identifier.other | AAINN87498 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/55367 | |
| dc.description | The non-linear (approximately quadratic) response has been the one major impediment to the use of the flame photometric detector (FPD) for the gas chromatography (GC) of organosulfur compounds. Two and half decades after the introduction of the GC-FPD, a linear sulfur emitter has finally been found, and is introduced in this thesis. The new emitter produces a linear response over four orders of magnitude. The minimum detection limit reaches 7 $\times$ 10$\sp{-13}$ mol S/s at S/N = 2. | en_US |
| dc.description | In this thesis, a variety of organometallic compounds containing transition metals--Ru, Ni, Mn, Fe, Os, Re, Mo and Co--have been determined by GC-FPD. The responses have been optimized for individual elements. In a filter-less mode, and at optimized conditions, the detection limits (S/N = 2) range from 2 pg or 1 $\times$ 10$\sp{-15}$ mol/s for ruthenocene to 5 ng or 3 $\times$ 10$\sp{-12}$ mol/s for cobaltocene. All these transition elements respond in a linear manner. The elemental selectivities vis-a-vis carbon in the filter-less mode range from 4 $\times$ 10$\sp5$ (for ruthenium) to 1.5 $\times$ 10$\sp2$ (for cobalt). The quenching effects caused by co-eluting hydrocarbon compounds are negligible. The FPD spectra of these transition metals, some main-group elements, and several types of carbon compounds are obtained at analytical conditions. A variety of atomic (as opposed to molecular) transitions are found to occur from levels as high as 3.6 eV above ground state. | en_US |
| dc.description | The selectivities of various transition elements against hydrocarbons have been defined in (1) single-channel filter-less, (2) single-channel filter, and (3) dual-channel differential modes. The metal-carbon selectivities are improved by one to two orders of magnitude by operating the detector not in the conventional single-channel filter mode but in the dual-channel differential mode. The latter mode makes it possible to increase the selectivity of one hetero-element over the other; and to distinguish between two hetero-elements by oppositely directed peaks in a matrix of carbon compounds. | en_US |
| dc.description | A further dual-channel selective mode-conditional access (CONDAC) chromatography--has also been developed and tested. CONDAC is able to generate chromatograms which are nominally specific (infinitely selective) for any chosen FPD-active element. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 1993. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Chemistry, Analytical. | en_US |
| dc.title | New elements and response modes in flame photometry. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
