14results about How to "Small dead volume" patented technology

The semiconductor pressure reducing valve comprises a valve body, a rear cover, a lock nut and a handle, the tail end of an inlet channel of the valve body is arranged to be of a reducing opening structure, a valve body is arranged in the inlet channel, the upper portion of the valve body is connected with a valve body valve rod, and the upper end of the valve body valve rod is fixedly connected with the bottom of a membrane head connecting block; a spring pressing block, a buffer spring, a diaphragm head, a diaphragm pressing block and a diaphragm are sequentially arranged in the rear cover from top to bottom, the outer periphery of the diaphragm is fixed between the diaphragm pressing block and the upper end of the valve body, the inner periphery of the diaphragm is fixedly connected with the lower portion of a diaphragm head connecting block, and the upper portion of the diaphragm head connecting block is fixedly connected with the bottom of the diaphragm head. By improving the structure of the valve body, a spring on the lower portion of the valve body is omitted, and it is guaranteed that a medium channel is closed in a non-working state by means of fixed connection of the membrane head connecting block and the valve rod of the valve body; opening of the medium channel is guaranteed by rotating the handle and pressing down the valve rod of the door body, the dead volume in the medium channel is greatly reduced, the problems of gas residue and adsorption are solved, and favorable conditions are provided for meeting the requirement for gas cleanliness.

The invention belongs to the technical field of electrodialysis, and particularly relates to a material-cylinder-free continuous multistage countercurrent electrodialysis system and an electrodialysis method. The material-cylinder-free continuous multistage countercurrent electrodialysis system comprises more than two stages of membrane stacks, each compartment of each stage of membrane stack is not provided with a material cylinder, and the compartments of each stage of membrane stack are directly connected through pipelines. The feed liquid in each compartment of each stage of membrane stack in the electrodialysis system is organized in a countercurrent manner, and in-stack self-circulation of the feed liquid in each compartment is realized through a circulating pump. The system is simple, convenient to connect, quick to start and quick in dynamic response. The interstage flow is stable, and the whole system is convenient to control.

The invention discloses an emulsion preparation device and an emulsion preparation method using the same, the device comprises a mixer main body, a liquid inlet conduit, a liquid outlet conduit and a feeding assembly, the mixer main body has a three-way flow channel structure, an optional flow channel is a liquid outlet flow channel, the other two flow channels are liquid inlet flow channels, the liquid outlet conduit is communicated with the liquid outlet flow channel, and the feeding assembly is communicated with the liquid inlet flow channel. The liquid inlet guide pipe is communicated with the liquid inlet flow channel, and the feeding assembly is communicated with the liquid inlet guide pipe. The method for preparing the emulsion comprises the steps that the dispersed phase and the mobile phase are obtained, the continuous phase and the dispersed phase are put into the two liquid inlet flow channels of the mixer body through the liquid inlet guide pipes by means of the feeding assembly, the emulsion formed after mixing flows out of the liquid outlet flow channels and is collected, the flow speed ratio of the continuous phase to the dispersed phase is 2: 1-4: 1, and the total flow speed is 60-750 mL / min. According to the scheme, the emulsion with the appropriate particle size is prepared at the low flow speed, the feeding temperature range is wide, the device is simple, the channel dead volume is small, and the device is suitable for both laboratories and industrial production.

This invention discloses a laboratory-grade ceramic membrane pressure filtration device, comprising a pressure ceramic membrane filtration unit, a pressure pump, a feed container, a valve, and a dialysate container. This invention uses an inorganic ceramic membrane as the filter medium, which is resistant to acids and alkalis, resistant to organic solvents, has a wide range of applications, high strength, and high operating pressure. It maintains high membrane integrity during installation, disassembly, and filtration, and offers high operating flux and high recovery rate. It can withstand both high-pressure steam sterilization and chemical sterilization. The sealing method is simpler than that of tubular ceramic membranes, and the dead volume is significantly smaller, requiring relatively less feed solution, making it suitable for laboratory operating environments.

The invention discloses a plunger pair liquid film pressure testing device for a high-pressure plunger pump. The plunger pair liquid film pressure testing device comprises a testing cavity assembly, a liquid film pressure testing assembly and a signal acquisition module. The testing cavity assembly is connected with a high-pressure plunger pump plunger pair, positions a plunger cavity to be tested and drains liquid in the plunger cavity to be tested to the multiple liquid film pressure testing assemblies. The plurality of liquid film pressure test assemblies respectively collect liquid film pressure signals of a plurality of plunger axial set points between plunger pairs of the high-pressure plunger pump. And the signal acquisition module extracts each liquid film pressure signal to obtain the liquid film pressure of each set point position in the axial direction of the plunger. According to the invention, the dead volume of the pressure sensor cavity can be effectively adjusted, the liquid film cavity can be amplified, the axial liquid film pressure between the plunger pairs can be obtained through testing, residual air in the sensor cavity can be discharged, the static pressure cavity is ensured to be filled with the liquid film, and accurate extraction of the liquid film pressure is realized.

The invention provides a pumping detection TAP instrument, and relates to the field of transient dynamics and catalytic surface and interface research. The pumping detection TAP instrument provided by the invention comprises a sample injection pulse system, a micro reactor, a liquid nitrogen cooling system, a mass spectrum system and a vacuum system. Through the arrangement, the experiment of continuous pulse or intermittent pulse or pump-probe pulse of one or two gas molecules can be realized, so that surface chemistry and microdynamics information related to element steps can be obtained.

The utility model discloses a kind of for gas chromatograph gas quantitative manual sampling auxiliary device, including three-way valve, the first joint of three-way valve is connected with sampling tube, sampling tube is connected with sampling needle, the second joint of three-way valve is connected with gas inlet pipe, gas inlet pipe is connected with gas chromatograph, the third joint of three-way valve is connected with ferrule joint by connecting pipeline, ferrule joint side is connected with quantitative ring, the utility model is connected with sampling needle by sampling tube, the second joint of three-way valve is connected with gas inlet pipe, gas inlet pipe is connected with gas chromatograph, the third joint of three-way valve is connected with ferrule joint by connecting pipeline, ferrule joint side is connected with quantitative ring, the utility model is by using fixed volume quantitative ring as sampling unit, sampling volume only depends on the geometric volume of quantitative ring, unrelated with the manual extraction action of operator. Compared with the volume deviation caused by reading error, uneven pulling speed in the sampling mode of traditional syringe, fundamentally eliminate the influence of human factor, ensure that sampling volume is constant each time, greatly improve the accuracy and reliability of quantitative analysis.

This invention discloses a tangential flow filtration separation device and a method for determining the drug content of liposomal drugs, relating to the field of liposomal drug filtration and determination technology. The device includes a filtration separation component, a gas control component, a drive component, and system piping and valve components. The filtration separation component includes a porous membrane filtration unit, with the inner cavity of the membrane forming a mother liquor flow path, and the outer cavity connected to a filtrate collection unit. The drive component is connected to the mother liquor flow path, and the gas control component is also connected to the mother liquor flow path. The system piping and valve components connect the filtration separation component, the gas control component, and the drive component to form a closed-loop flow path. This invention solves the problems of existing methods, such as difficulty in efficiently and stably separating free drugs from liposomal components, cumbersome operation, easy liposomal leakage, and sample loss and dilution, which seriously affect the accuracy of detection.

The present invention discloses a hard-sealed high-purity gas pressure reducing valve, comprising a lower valve body, a rear cover connected to the lower valve body by threads, an upper valve body arranged between the rear cover and the lower valve body, the top of the upper valve body tightly connected to the rear cover by a pressure block, and the bottom of the upper valve body tightly connected to the lower valve body by a metal O-ring and a metal C-ring; a diaphragm is arranged on the top of the upper valve body, the diaphragm is connected to a pressure regulating spring, one end of the pressure regulating spring is connected to a top screw passing through the rear cover; a valve needle is arranged in the lower valve body, one end of the valve needle contacts the bottom of the diaphragm, and the other end is connected to the lower valve body by a small spring. The hard-sealed high-purity gas pressure reducing valve provided by the present invention has good sealing surface elasticity and high sealing precision.

The continuous preparation apparatus and process for glucosamine sulfate or phosphate compounds described in this invention comprises at least three chromatographic separation units connected in a specific manner to form a continuously operable closed-loop system. Each separation unit is connected via pipelines to a chromatographic column, a delivery pump, a switching valve, and a feed tank. The switching valve controls the flow direction of the feed liquid, solution, water, and waste liquid, creating a dual-function system capable of operating independently or in conjunction with other separation units. This invention utilizes a real-time dynamic axial compression column, significantly reducing the dead volume at the column head, thereby improving both separation efficiency and the concentration of glucosamine sulfate or glucosamine phosphate solutions. The alternating use of alkali and acid, along with a matching preparation process, activates weak base exchange groups to achieve exchange capacity similar to strong base exchange groups, while also promptly removing impurities adsorbed on the packing material, thus improving product quality. The entire process is a closed-loop, continuous operation via pipelines, facilitating automated control.

The invention provides an electrochemical flow cell device for near-normal-pressure X-ray photoelectron spectroscopy in-situ testing, and relates to the field of near-normal-pressure X-ray photoelectron spectroscopy experimental instruments. The electrochemical flow cell device for the near-normal-pressure X-ray photoelectron spectroscopy in-situ test comprises a fixing mechanism and an electrochemical in-situ cell arranged on the fixing mechanism, and the electrochemical in-situ cell is located in an APXPS cavity; the electrochemical in-situ pool sequentially comprises a front plate, a gold net, an ion exchange membrane, an insulating plate, a back plate and two gas-liquid sample introduction pipes which are detachably connected, and the back plate is detachably connected with the fixing mechanism; the ion exchange membrane is coated with a sample, a light inlet through hole is formed in the front plate, a gas-liquid channel is formed in the back plate, and the two gas-liquid sample injection pipes penetrate through the fixing mechanism to be connected with the back plate and are communicated with an inlet and an outlet of the gas-liquid channel respectively. According to the invention, the real-time observation of the electrode surface species and the catalyst valence state is realized under the near-normal-pressure condition.

The invention discloses a preparation method of a colorimetric sensor for gas chromatography, which comprises the following steps: dissolving dye by using a thin layer chromatography silica gel plate as a substrate and ethanol as a solvent to enable the dye to be attached to the substrate, and blow-drying. The invention also provides a gas analysis system which comprises a sample injection subsystem, a carrier gas subsystem, a capillary chromatographic separation column system, a colorimetric sensing subsystem and a data analysis subsystem. According to the invention, gas chromatography and a video data extraction program can be combined, the visual detection of a gas analyte sample can be conveniently realized, the miniaturization of a gas detection and analysis system is facilitated, and a new thought and direction are provided for the development of a miniature gas chromatograph detector.

The invention discloses a 3D printing pump-free sample injection point discharge atomic emission spectrum analysis device and method for detecting arsenic, and belongs to the technical field of atomic emission spectrum analysis. Comprising a 3D printing integrated device, an external gas path system and a spectrum detection system, the 3D printing integrated device comprises a 3D printing module, a quartz glass sheet, a quartz capillary tube, two tungsten filament electrodes and a microsyringe; the external gas path system comprises a small argon steel cylinder, two argon pipelines, a gas flow meter and a trace gas flow meter; the spectrum detection system comprises an optical fiber and a small CCD spectrometer. The method comprises the following steps: injecting an arsenic-containing solution sample into a reaction chamber of a 3D printing device by using a microsyringe, converting the arsenic-containing solution sample into a gaseous analyte through hydride generation, blowing the gaseous analyte into a discharge chamber by argon, exciting an atomic emission spectrum of arsenic by using micro plasma, radially collecting a spectral signal from the outside of a quartz capillary by using a bare optical fiber, and transmitting the spectral signal to a CCD (Charge Coupled Device); and finally, the concentration of the arsenic in the sample can be obtained through calculation. The method has the characteristics of high excitation efficiency, strong anti-interference capability, low cost, open source sharing, environmental friendliness and the like.

This utility model relates to the technical field of chemical process monitoring equipment, specifically a time-sharing oxygen concentration monitoring device for dual reactors. It has two symmetrically distributed sampling branches, each equipped with a reactor. A common gas path module is located outside the sampling branches, including three-way solenoid valves V1 and V2, a main solenoid valve VT, and purge gas systems connecting V1, V2, and VT respectively. The main solenoid valve VT is also connected to an oxygen analyzer. This utility model mainly achieves pollution-free switching monitoring of two reactors by a single oxygen analyzer through a symmetrical three-way valve group and a positive pressure isolation structure, reducing equipment investment and operation and maintenance costs, improving instrument lifespan and analytical efficiency, and simultaneously reducing the probability of direct equipment damage.