摘要:
In one embodiment the invention is a method for on-column valved injection gas chromatography by on-column injecting more than 5 microliters and less than one milliliter of sample consisting of a solvent and a component of interest into a retention gap/capiliary column system with an injection valve at a first carrier gas flow rate, followed by a substantially higher carrier gas flow rate to blow the solvent of the sample out of the system at a rapidly increased rate and then a return to a lower flow rate to chromatograph the component of interest. In another embodiment, less than 5 microliters of sample consisting of a solvent and a component of interest is on-column injected into a capillary column using an injection valve and a relatively high column inlet pressure of gas to move the sample from the injection valve into the colunm rapidly and with reduced carryover. Then, the pressure of carrier gas is reduced to a normal pressure for chromatography of the component of interest.
摘要:
Method and apparatus for gas chromatography/mass spectroscopy including a retention gap, a capillary gas chromatography column and a mass spectrometer, the improvement being a valve that facilitates temporarily venting the carrier gas from between the retention gap and the capillary gas chromatography column immediately after the injection of a sample. The valve also facilitates an alternate flow of carrier gas into the mass spectrometer during the venting operation.
摘要:
A method for on-column injection of large sample volumes using the retention gap technique in capillary gas chromatography for sample components of interest that would be obscured by the large solvent peak otherwise inherent in the technique. This interference from the large solvent peak is removed by venting carrier flow from the retention gap to waste for a limited time, long enough to discard much of the solvent without serious loss of the sample component of interest.
摘要:
The invention describes a large volume on-column gas chromatographic method for analyzing trace levels of high molecular weight and polar compounds in a sample and an apparatus for performing the method. A column inlet coupled to an analytical column is heated rapidly to concentrate difficult to chromatograph compounds onto the analytical column resulting in an increase in the detectability of the compounds.
摘要:
The present invention generally relates to an apparatus and method for running a plurality of essentially simultaneous exothermic reactions, endothermic reactions, or a combination thereof in sealed reactors and obtaining physico-chemical data, preferably temperature data, and, optionally, time data, for the reactions, wherein reaction mixtures in the sealed reactors are adiabatically thermally insulated from one another so that temperature in one sealed reactor does not materially affect temperature in any other, including an adjacent, sealed reactor.
摘要:
The viscosity or relative viscosity of samples can be measured in parallel by dispensing or aspirating the samples at a set condition and then measuring a property of the sample such as mass dispensed or aspirated.
摘要:
The present invention generally relates to a coating apparatus and method for substantially simultaneously forming a plurality of coatings on a substrate and to a method of analyzing at least one characteristic or property of the coatings.
摘要:
The invention provides, in one embodiment, a device for performing scrub testing on a plurality of samples simultaneously, including a plurality of scrubbing devices. A stage is provided which positions the plurality of samples in contact with the plurality of scrubbing devices. The scrubbing devices can individually be provided with different weights to produce different forces on the samples. A motion producing device produces one or both of linear and rotational motion between the brushes and the samples. The scrubbing devices are held in the stage so as move freely vertically.
摘要:
The present invention generally relates to a coating apparatus and method for substantially simultaneously forming a plurality of coatings on a substrate and to a method of analyzing at least one characteristic or property of the coatings.
摘要:
The invention provides, in one embodiment, a device for performing scrub testing on a plurality of samples simultaneously, including a plurality of scrubbing devices. A stage is provided which positions the plurality of samples in contact with the plurality of scrubbing devices. The scrubbing devices can individually be provided with different weights to produce different forces on the samples. A motion producing device produces one or both of linear and rotational motion between the brushes and the samples. The scrubbing devices are held in the stage so as move freely vertically.