37 results about "Micro gas chromatography" patented technology

Improved micro-columns and methods for producing micro-columns particularly suitable for use in gas chromatographs are disclosed. In particular, following deposition of the stationary phase coating, the micro-columns are subjected to a postcoating treatment with a molecule that binds to the active sites in the stationary phase micro-column thereby eliminating or reducing loss of gas chromatograph performance associated with those active sites. The postcoating treatment molecule binds to the same active sites as the analytes of interest.

The invention refers to miniature gas-chromatograph field based on the micro-processing technique. It provides a gas-chromatograph column, including at least two cover layers and a gas-way layer, each layer material is compact, two sides of the gas-way layer both have micro-processed troughs, one side of the trough and the cover layer at least forms two capillaries, the capillaries are linked to form a complete one through the open hole in the gas-way layer, the complete capillary links to the exterior at two bottoms through the open holes of two most outer cover layers, one entrance and the other exit.

The invention discloses a miniature gas chromatographic column integrated chip with rapid separation function, and relates to gas chromatographic column integrated chip technology. The integrated chip includes a miniature chromatographic column, combined miniature heaters, and combined miniature temperature sensors. Miniature chromatographic column channels are formed on a silicon substrate by deep etching or chemical etching based on microelectromechanical system (MEMS) technology, then the silicon substrate is hermetically bonded with glass to form the miniature chromatographic column; before bonding, the combined miniature heaters are integrated in the channels and the substrate bottom where the channels are located; and through combined heating, rapid temperature rise is realized, and separation speed and separation performance of the miniature chromatographic column are improved. Meanwhile, the combined miniature temperature sensors are integrated on the upper and the lower surfaces of the channels and in the channels of the miniature chromatographic column, to real-time respond temperature of a gas sample in the miniature chromatographic column, thereby facilitating heating state adjustment of the miniature heaters by an external control circuit, controlling temperature of the miniature chromatographic column, and enabling the miniature chromatographic column to achieve rapid separation, and excellent total separation performance is realized.

A method for preparing hydrogen from thermochemical reaction of sludge comprises the steps: putting crushed dry sludge and a sodium hydroxide solid into an alumina magnetic boat, and mechanically stirring to make the two components mixed evenly; putting the alumina magnetic boat into a tubular furnace, introducing nitrogen gas, making the tubular furnace full of nitrogen gas, and connecting an outlet of the tubular furnace with a condensing device; starting a reaction, continuously introducing nitrogen gas in the reaction process, and providing an inert pyrolysis atmosphere; setting a tubularfurnace heating program, staring up the tubular furnace, and maintaining for a certain time after the final temperature is reached; and collecting gas from the rear of the condensing device in the reaction process. The invention also provides a system for preparing hydrogen from the thermochemical reaction of the sludge, wherein the system comprises the tubular furnace; the outlet of the tubular furnace is connected with the condensing device; a gas outlet of the condensing device is connected with a gas collecting bag and a micro gas chromatograph analytical instrument with a micro gas chromatograph analytical result output display screen via a three-way valve. The method and system have the advantages of easily obtained raw materials, short hydrogen production process, simple operation and effective absorption of greenhouse gas under high temperature pyrolysis conditions.

The invention discloses a micro gas chromatography column that can use air as a carrier gas and a manufacturing method thereof, which comprises the steps of forming an aluminum mask layer by photolithography peeling on a silicon wafer; ; Soak the silicon wafer in acid solution, remove the mask and bond with borosilicate glass; sputter titanium and platinum on the back of the silicon wafer as temperature measuring resistance, heating wire and electrode; sputter gold as electrode pins; capillary connection to micro gas chromatography The column has two ports; mesoporous silica microspheres are constructed in the microfluidic channel of the chromatographic column, and the ionic liquid stationary phase is coated by static coating. The mesoporous structure in the chromatographic column greatly increases the coating area of ​​the stationary phase, improves the separation ability within the limited length of the chromatographic column, has a good tolerance to oxygen, and ensures the high reliability of the micro-chromatographic column in a high-temperature aerobic environment It has high stability, high stability and high column efficiency, and can directly use air as the carrier gas, providing an excellent micro-chromatographic column for the VOCs detection system.

The invention provides a silicon-based micro-gas chromatographic column with high separation efficiency and a preparation method thereof. The preparation method includes: 1) making a microchannel and a microfluidic port on a silicon substrate; 2) making a mask layer to protect The bonding surface on the silicon substrate; 3) constructing nanometer mesoporous silicon oxide in the micro-channel; 4) bonding a packaging cover plate to the bonding surface of the silicon substrate; 5) based on The components to be separated form corresponding modification materials on the surface of the nanometer mesoporous silicon oxide. Since nano-mesoporous silica has a large specific surface area and pore volume, and has good thermal stability and mechanical strength, the present invention constructs it in a silicon-based micro-gas chromatography column, which can greatly improve the separation of the chromatographic column. Efficiency: The surface of nanometer mesoporous silicon oxide has a high density of silanol (Si‑OH), which can further construct a monomolecular layer with different separation functions on the surface according to the different separation objects to achieve the desired separation effect.

The invention discloses a high-aspect-ratio micro gas chromatographic column and a manufacturing method thereof by wet etching. The micro gas chromatographic column is made on a (110) single crystal silicon substrate to form a broken-line chromatographic groove, and the long and short sides of the broken line are The included angle is 70.53°, which are along the <110> and <112> crystal directions of the substrate, respectively. The zigzag chromatographic column adopts an anisotropic wet etching method to prepare vertical deep grooves with a high aspect ratio, and then is bonded with silicon glass, so that the entire zigzag groove has a high aspect ratio, and in a small area to achieve a sufficiently long column length. In terms of characteristic dimensions such as aspect ratio, column length, area, etc., the zigzag deep groove prepared by the present invention is equivalent to the vertical deep groove processed by DRIE, but the wet etching processing method adopted is simple and easy, and does not need to use expensive DRIE etching equipment greatly reduces processing costs.

The invention discloses a micro-chromatograph underwater beam tube monitoring system. The system comprises underground equipment and ground equipment. The ground equipment comprises a communication control device, and the underground equipment comprises a detection analysis portion and a beam tube sampling portion and is connected with the ground communication control device through a network. The detection analysis portion comprises a miniature gas chromatograph, a standard gas sample feeding control treatment device, a sample gas feeding and drying control treatment device and a carrier gas supply control device. The beam tube sampling portion comprises an intrinsic safety gating combined control device. The micro-chromatograph underwater beam tube monitoring system has advantages that online automatic high-precision real-time monitoring of gas contents of underground monitoring points is directly realized in an underground environment; unattended long-term reliable operation of the chromatograph is realized; network sharing of monitoring data results is realized; by adoption of an explosion-proof technique, operational reliability and normality in a flammable and combustible environment can be guaranteed, and adaptability to positive-pressure or negative-pressure sample gas collection modes is realized.

The invention provides a minisized gas-chromatographic-column chip and a preparation method thereof. The chip comprises at least two mutually-independent chromatographic channels, which are filled with stationary phases in different phase states; at least one connecting channel, which is connected with and located between two adjacent chromatographic channels and used for realizing communication between two adjacent chromatographic channels; and at least one solenoid valve, which is arranged in one connecting channel and used for opening or closing the connecting channel to enable gas to flowthrough the two chromatographic channels communicating with each other via the connecting channel when the connecting channel is opened. According to a scheme of the invention, usage of a single chromatographic channel or combined usage of a plurality of chromatographic channels can be realized through opening or closing of the solenoid valves, so active selection can be performed according to ambient gas; i.e., the chromatographic channels can be filled with a plurality of stationary phases; and thus, the variety of separated gas is greatly increased, and combined usage of a plurality of chromatographic columns is not needed for mixed gas with complicated background, which enables the size of a system to be greatly reduced.