The disclosure relates to microchemical (or microfluidic) apparatus as well as related methods for making the same. The methods generally include partial sintering of sintering powder (e.g., binderless or otherwise free-flowing sintering powder) that encloses a fugitive phase material having a shape corresponding to a desired cavity structure in the formed apparatus. Partial sintering removes the fugitive phase and produces a porous compact, which can then be machined if desired and then further fully sintered to form the final apparatus. The process can produce apparatus with small, controllable cavities shaped as desired for various microchemical or microfluidic unit operations, with a generally smooth interior cavity finish, and with materials (e.g., ceramics) able to withstand harsh environments for such unit operations.

Burner assemblies of flame-based detectors are configured to deliver decompressed mobile phase of supercritical fluid chromatography systems to the flame of a flame-based detector while providing for improved optimization of analyte response as well as enhanced flame stability during operation.

Burner assemblies of flame-based detectors are configured to deliver decompressed mobile phase of supercritical fluid chromatography systems to the flame of a flame-based detector while providing for improved optimization of analyte response as well as enhanced flame stability during operation.

Provided is a system comprising a conduit from a gas chromatograph column to a single reactor comprising a Fe, Co, Pt, Ni, Rh, Pd and/or Ru catalyst(s), with hydrogen and oxygen feed conduits for providing hydrogen and oxygen to the reactor, and a conduit from the reactor to an FID detector. This allows one to practice a method for the detection and quantification of organic molecules from a gas chromatograph which comprises passing the effluent from a gas chromatograph column to a reactor comprising a Fe, Co, Pt, Ni, Rh, Pd and/or Ru catalyst; adding hydrogen and air/oxygen to the reactor; reacting the effluent from the gas chromatograph column in the reactor to sequentially oxidize then reduce all organic containing molecules to CH.sub.4 by heating to an elevated temperature, and passing the reactor effluent to an FID.

Provided is a system comprising a conduit from a gas chromatograph column to a single reactor comprising a Fe, Co, Pt, Ni, Rh, Pd and/or Ru catalyst(s), with hydrogen and oxygen feed conduits for providing hydrogen and oxygen to the reactor, and a conduit from the reactor to an FID detector. This allows one to practice a method for the detection and quantification of organic molecules from a gas chromatograph which comprises passing the effluent from a gas chromatograph column to a reactor comprising a Fe, Co, Pt, Ni, Rh, Pd and/or Ru catalyst; adding hydrogen and air/oxygen to the reactor; reacting the effluent from the gas chromatograph column in the reactor to sequentially oxidize then reduce all organic containing molecules to CH.sub.4 by heating to an elevated temperature, and passing the reactor effluent to an FID.

A method for detecting an analyte in a chromatography system includes performing a separation using a mobile phase that includes an organic component. The separation is performed with a primary separation module such as a chromatographic column. A first effluent, from the primary separation module, is modulated so that a fluidic plug containing an amount of the organic component and an analyte is provided to a secondary separation module where a secondary separation is performed. A second effluent, from the secondary separation module, includes temporally-resolved organic component and analyte peaks due to selective retention of the analyte. The second effluent is provided to a flame-based detector which is disabled when the organic modifier peak is received and enabled at least during the time when the analyte peak is received. Thus the analyte can be detected without interference from any response of the detector to the organic component peak.

A method for detecting an analyte in a chromatography system includes performing a separation using a mobile phase that includes an organic component. The separation is performed with a primary separation module such as a chromatographic column. A first effluent, from the primary separation module, is modulated so that a fluidic plug containing an amount of the organic component and an analyte is provided to a secondary separation module where a secondary separation is performed. A second effluent, from the secondary separation module, includes temporally-resolved organic component and analyte peaks due to selective retention of the analyte. The second effluent is provided to a flame-based detector which is disabled when the organic modifier peak is received and enabled at least during the time when the analyte peak is received. Thus the analyte can be detected without interference from any response of the detector to the organic component peak.

The present disclosure relates to an oxidizer, and related methods, for oxidizing polar modifiers in chromatographic mobile phases. The oxidizer enables the use of flame-based detection in chromatographic separations, such as carbon dioxide based chromatography, which employ polar modifiers, such as methanol. Upon exiting a chromatographic column, the mobile phase containing the polar modifier is flowed through an oxidizer that contains a catalyst to oxidize at least a portion of the polar modifier to a species that does not interfere with the function of the flame-based detector. The oxidizer allows for flame-based detection, such as flame ionization detection, in applications in which a polar modifier with a reduced form of carbon is used.

The present disclosure relates to an oxidizer, and related methods, for oxidizing polar modifiers in chromatographic mobile phases. The oxidizer enables the use of flame-based detection in chromatographic separations, such as carbon dioxide based chromatography, which employ polar modifiers, such as methanol. Upon exiting a chromatographic column, the mobile phase containing the polar modifier is flowed through an oxidizer that contains a catalyst to oxidize at least a portion of the polar modifier to a species that does not interfere with the function of the flame-based detector. The oxidizer allows for flame-based detection, such as flame ionization detection, in applications in which a polar modifier with a reduced form of carbon is used.

A high speed treatmenthigh throughput gas-chromatography system for analysis of high-molecular weight additives in a polymer material, and an analysis method using same are provided. A high throughput gas-chromatography system is capable of qualitatively and quantitatively analyzing, at the same time, high-molecular weight additives in a polymer, and reducing analysis time by increasing a heating rate and a column maximum temperature.