摘要:
The present invention relates to a method for injecting a sample (i.e. a material to be analyzed that may be dissolved in a solvent) in a vaporization chamber or in a pre-column or a gas chromatograper, this method implying separately injecting a co-solvent, with the co-solvent being injected in advance of the sample and/or in a point in the vaporization chamber other than the sample injection point.
摘要:
The present invention relates to a method for injecting a sample (i.e. a material to be analyzed that may be dissolved in a solvent) in a vaporization chamber or in a pre-column or a gas chromatograper, this method implying separately injecting a co-solvent, with the co-solvent being injected in advance of the sample and/or in a point in the vaporization chamber other than the sample injection point.
摘要:
A method and an apparatus for chromatography are described, wherein at least one element in electrically conductive material is provided to heat the capillary column in a direct way and wherein the control of the temperature is carried out according to a mathematical model having a component of predictive type, or Feed Forward type, that describes the thermodynamic behavior of the assembly comprising the electrically conductive element and the column at least as a function of the thermal resistance and the thermal capacity of the assembly thus constituted in order to regulate the supply of electrical power supplied to the conductive element.
摘要:
The invention concerns a device for vaporizing injections of samples into a gas chromatography analysis device, comprising a vaporization chamber elongated lengthways and heated, as well as a syringe equipped with a needle, the device being of the type in which the introduction of the sample is carried out without prior vaporization of the sample within the needle, and also foresees at least one stop and vaporization means for the liquid inside the vaporization chamber. To improve the conditions of vaporization and the transfer of the sample, the distance between the free end of the needle and the stated stop and vaporization means for the liquid is greater than 55 mm (FIG. 1).
摘要:
A method and device for vaporization injection in which there is at least one constriction between the end of the sample injection needle or tube and the interior of the heated vaporization chamber. The terminal part of the needle or tube can be heated to improve nebulisation of the sample and therefore its vaporization speed.
摘要:
A vaporization injector for gas chromatography analysis instruments, of the type including a vaporization chamber, heated or which may be heated, with a longitudinally elongated shape, a device for hermetically inserting the needle of a syringe containing the sample (substance to be analysed and solvent) into the chamber, a connection for feeding a carrier gas into the chamber and a gas chromatography capillary column with an upstream end open inside the vaporization chamber. In order to allow the vaporization of large sample volumes, the upstream end of the gas-chromatography column and the injection point of the sample into the vaporization chamber are both arranged adjacent to one of the longitudinal ends of the vaporization chamber and the feed connection for the carrier gas is located adjacent to the other end.
摘要:
The invention concerns a method and an apparatus for the direct injection of large volumes (>3 &mgr;l) of samples into the column in a gas chromatography analysis apparatus comprising an oven, a gas chromatography column lodged in the oven, a means for the direct transfer into the column of the sample and a source of carrier gas upstream the column, as well as a detector downstream the column. According to the invention two or more of the parameters: nature of the solvent injection rate flow-rate and/or pressure of the carrier gas temperature at least of an initial length of the column during the injection are correlated and/or controlled to achieve a control of the length of the zone wetted by the sample during its introduction.
摘要:
A device and method are described for the gas chromatographic separation of a sample, aimed in particular at the analysis of large volume samples. Provision is made for the use of calculating and memorizing a plurality of reference values corresponding to the evaporation rates of solvents combined with a carrier gas for a corresponding plurality of discrete values representing the conditions of pressure, temperature, injected sample volume and sample injection rate. The effective solvent evaporation rate is then calculated in correspondence to the effective conditions in which the process is carried out to determine the volumetric fraction of the sample which is transferred through the capillary column in relation to its characteristics and geometrical dimensions.
摘要:
There is provided a method and apparatus for controlling the carrier gas flow through a gas chromatographic apparatus with capillary column subjected to variations in temperature, through control of feeding pressure achieved following computerized processing of the equation of the carrier flow rate as a function of inlet pressure, column temperature and system structural parameters, including preliminary determination of the system parameters through detection of pressure, temperature and flow rate values in stabilized conditions of carrier passage through apparatus and calculation of a constant representing said parameters on the basis of values detected and in application of the aforesaid equation; storage of aforesaid constant; utilization of constant in the mentioned equation for controlling carrier flow rate through calculation and control of its feeding pressure during utilization of the gas chromatographic apparatus.
摘要:
The invention relates to a vaporization injector for a gas chromatograph, said injector comprising a structure (11) mounted in a detachable manner on the gas chromatograph body and including the sample introduction means, the vaporization chamber and pneumatic connections for feeding the carrier gas to the vaporization chamber and to the septum purge means, as well as pneumatic connections for evacuating the splitted sample and carrier gases.