80 results about "Laboratory flask" patented technology

The invention relates to the technical field of electrophoretic display, in particular to a preparation method of black electrophoretic particles with low reflectivity and high charge quantity. The method comprises the following steps: S1, mixing pre-dried black electrophoretic particles with ethanol, water and zirconium beads, adjusting the pH value by using ammonia water, and carrying out ball milling; transferring to a four-neck flask, adding a silane coupling agent, adjusting the pH value again, reacting at 80 DEG C, washing, centrifuging and drying to obtain modified particles; s2, carrying out ball milling on the modified particles, a monomer 1, a monomer 2 and a solvent, transferring into a four-neck flask, heating to 50 DEG C under the protection of nitrogen, adding an initiator, and reacting at 70-85 DEG C; after cooling, adding 3-5 parts of monomers and a solvent, repeatedly heating, adding an initiator, and reacting at 70-85 DEG C; and cooling again, supplementing the monomer 2 or 3, reacting under the same condition, and finally centrifuging, washing and drying to obtain the modified electrophoretic particle with the controllable shell structure. According to the invention, controllable regulation and control of low reflectivity and high charge quantity of the black electrophoretic particles are realized.

The utility model discloses a distillation instrument which comprises a rack, a heating bowl is mounted at the top of the rack, a flask is arranged at the top of the heating bowl, a receiving bottle is arranged at the bottom of the rack, a condensation pipe is communicated with the top of the receiving bottle, the top of the condensation pipe is communicated with the flask, a controller is arranged in the rack, and the controller is connected with the heating bowl. A distillate metering assembly is arranged on one side, close to the receiving bottle, of the rack. The distillation temperature and the weight of distillate are sensed in real time and compared with values such as the distillation temperature and the distillation speed which are input in advance, the heating power of the heating bowl is automatically adjusted, automatic adjustment and control over the distillation temperature and the distillation speed are achieved, the automation rate of the distillation instrument is increased, manual intervention is not needed in the distillation process, and the production efficiency is improved. The stability of the distillation temperature and the distillation speed in the distillation process is improved, so that the distillation efficiency and the sample purity are improved.

The utility model discloses an integrated collection device for waste oil in a laboratory, and belongs to the technical field of waste oil collection and treatment. The turning cover is rotationally connected to the funnel; the mesh screen is detachably connected in the funnel; the diversion pipe is in threaded connection with the bottom of the funnel; the connecting plate is in threaded connection with the connecting ring; the breather pipe is fixedly connected to the connecting ring; according to the utility model, the funnel is fixedly arranged on the waste oil collecting barrel through the device, so that the funnel does not need to be taken down to seal the cover, on one hand, the problem that oil is easy to drip when the funnel is taken out is solved, and on the other hand, the problem that a barrel cover is difficult to open by a single hand when a worker pours round-bottom glass instruments such as a distillation flask and a test tube in the prior art is solved; meanwhile, through the turning cover arranged on the funnel, the problem that in the prior art, waste oil remaining on the funnel is prone to volatilizing and polluting the environment is solved.

The utility model relates to the technical field of chemical reagent experiments, in particular to a flask with an explosion-proof function, which comprises a safety plug, the bottom end of the safety plug vertically penetrates through an opening at the top end of a thin bottle neck, a ball bottle body is arranged at the bottom end of the thin bottle neck, and a pressure relief through pipe is arranged on the outer wall of one side of the ball bottle body. And a pressure relief valve obliquely penetrates through the interior of the pressure relief through pipe, one side of the outer portion of the ball bottle body is sleeved with a first protective net sleeve, and one side of the first protective net sleeve is connected with a second protective net sleeve in an adsorption mode. According to the improved flask and the safety plug, automatic pressure adjustment is achieved, a controllable pressure relief channel is formed, the sealing performance and the safety are balanced, the relative positions of the pressure relief valve and the pressure relief hole are changed, high-pressure gas can be conveniently diffused and discharged in a fan shape through the pressure relief hole, the impact force and danger of gas injection are reduced, meanwhile, the pressure relief valve has a reset mechanism, and the safety performance is improved. The first protective net sleeve and the second protective net sleeve can effectively intercept large glass fragments generated when the bottle body is broken, and the large glass fragments are prevented from splashing to hurt people.

The application relates to a functionalized glass for SERS detection and a preparation method thereof, characterized by the following steps: a. tetraethyl orthosilicate and oxalic acid are mixed into a 0.02-0.10 moL / L sol in anhydrous ethanol according to a molar ratio of 1:2-5, a stabilizer with a volume of 5-50% is added, and then the mixture is stirred and transferred into a four-necked flask; b. after being heated and stirred for 12-16 hours, an anhydrous ethanol emulsion of polystyrene small balls with a mass fraction of 5-20% and a volume of 6-18% is added; c. an anhydrous ethanol solution of a surfactant P123 with a total mass of 2-8% and a weight concentration of 3-8% is added, and then the mixture is stirred and aged; d. a wet film is prepared on a glass substrate, and then the wet film is dried and kept warm; (2) a nano-silver particle dispersion liquid with a concentration of 5-25 mg / mL is prepared; and (3) the glass substrate prepared in the step d is coated with the nano-silver particle dispersion liquid and dried. The application has the advantages of simple process and low cost; the surface of the porous structure silica nano-particles has a large number of nanoscale gap structures, which is beneficial to obtaining an enhanced silver nano-particle surface plasmon resonance electromagnetic field, and greatly enhances the Raman signal of the adsorbed molecules.

The utility model provides an electric heating jacket of avoiding corrosion, relates to the electric heating jacket field, including: heating base, heating cavity sleeve and flask, the lower end and outer side surface of flask attach heating base and heating cavity sleeve, the upper end of heating cavity sleeve is screwed with adjusting stud through fixed plate, the adjusting stud is connected with the hydraulic block of resistance through linking plate; a liquid guide cavity is formed in the upper end of the liquid blocking pressing block, an adsorption cotton block is bonded to the inner groove face of the liquid blocking pressing block, and the liquid blocking pressing block is in threaded connection with a liquid storage bottle through a mounting ring. The electric heating jacket solves the problem that power transmission is easily affected if a power supply connecting wire of the electric heating jacket is corroded by overflowing liquid in the prior art.

The triaxial sample preparation device based on the underwater deposition method comprises a saturator, a support, a water containing base, a vacuum pump and a three-valve mechanism, the saturator is a container used for vacuumizing and saturating underwater sandy soil, a pipeline connected with a pressure-resistant pipe is arranged on a top cover of the saturator, and a first valve is arranged on the top cover of the saturator to control on-off. The other end of the pressure-resistant pipe is connected with a vacuum pump. A pipeline connected with the rubber pipe is arranged below the saturator, and a second valve is installed to control on-off. The three-valve mechanism is a three-axis sample preparation mold, and a water containing base is installed above the three-valve mechanism. The saturator is fixed above the three-valve mechanism and the water containing base through a support. According to the device, the working procedure of preparing the triaxial sample by a traditional underwater deposition method is simplified, the working procedures of heating the sample, injecting air-free water, cooling overnight, transferring a sand solution between a flask and a funnel and the like are omitted, the sample preparation time is greatly shortened, the test operation threshold is reduced, and the test reliability is improved.

The utility model relates to the technical field of food pigments, in particular to a food pigment chemical inspection device which comprises an inspection device body, a flask is arranged in the inspection device body, a connecting pipe is arranged on the outer side of the flask, and a discharging hopper is arranged at the end, away from the flask, of the connecting pipe. A smashing assembly is arranged at the end, away from the connecting pipe, of the discharging hopper, and a filtering assembly is arranged in the connecting pipe. The crushing assembly is used for crushing the introduced food, the crushing assembly is composed of a connecting shell, an auger, a cutting knife and a connecting plate, the connecting shell is located in the inspection device body and located above the discharging hopper, the auger is rotationally connected to the interior of the connecting shell, the cutting knife is fixedly connected to the outer side of the auger, and the connecting plate is fixedly connected to the outer side of the connecting shell. Compared with the existing inspection device, the inspection device provided by the utility model has the advantage that the overall practicability of the inspection device can be improved through the design of the inspection device provided by the utility model.

The utility model discloses photochemical reaction equipment convenient to operate, which comprises a multi-neck flask, a glass spring tube, a peristaltic pump, a raw material cup, a flask frame, a blocking frame and an arc-shaped lamp top, the multi-neck flask is arranged on the upper end face of the flask frame, a connecting tube is arranged on the multi-neck flask, one end of the connecting tube penetrates through the outer side face of the multi-neck flask and then is arranged in the multi-neck flask, and the other end of the connecting tube is connected with the glass spring tube. The other end of the glass bourdon tube is communicated with one end of a peristaltic pump pipeline, the other end of the peristaltic pump pipeline is arranged in the raw material cup, the section of the blocking frame is in an L shape, the blocking frame corresponds to the glass bourdon tube in position, and the arc-shaped lamp top is arranged above the glass bourdon tube. The upper end face of the arc-shaped lamp top is fixedly connected with the lower end face of the L-shaped transverse section of the blocking frame, a plurality of illumination lamps are arranged on the arc-shaped lamp top, and the illumination lamps are in sliding connection with the lower end face of the arc-shaped lamp top. The beneficial effects of the utility model are that the experimental apparatus is simpler and more convenient so as to adapt to the teaching environment and enhance the cognition of the change of experimental conditions.

This invention discloses a shaker for a biochemical laboratory, comprising a main body and a bed surface mounted on the main body. A base plate is detachably mounted on the bed surface, and a vertically adjustable top plate is provided on the base plate. Multiple clamping drive mechanisms are evenly arranged between the top plate and the base plate. When the top plate is raised or lowered, each clamping drive mechanism is driven to operate simultaneously. This shaker for a biochemical laboratory differs from existing technologies in that, when using a biological shaker for cell culture, it can selectively choose a suitable clamping configuration based on the type of culture container, thereby providing effective shaking positioning for the culture container and ensuring stable and efficient shaking culture. Furthermore, during container placement and positioning, the top plate can be raised or lowered simultaneously to synchronously position or cancel the positioning of all containers on the top plate, eliminating the need for laborious flask clamp expansion to position each container individually.

The present application relates to an incubator, in particular to a multi-layer constant temperature oscillation incubator, comprising a constant temperature box, a box door, a partition, a guide rod and a sliding plate, the constant temperature box is hinged with the box door, the constant temperature box is connected with the partition, the constant temperature box is connected with the guide rod, the guide rod is connected with the partition, and the guide rod is connected with the sliding plate. The constant temperature box can keep the constant temperature environment, ensure the growth and reproduction of microorganisms in the most suitable conditions, the output shaft of the driving motor can drive the placement box to move up and down, the flask can produce oscillation, ensure that the nutrient components in the flask are evenly distributed, avoid local area nutrient excess or deficiency, the placement box can be moved up and down, the distance between the adjacent two placement boxes can be adjusted, the distance between the adjacent two placement boxes can be adjusted according to the height of the flask, the space inside the constant temperature box can be fully utilized, the space utilization rate is improved, and the waste of space is avoided.

Glass vessel (11, 11'), in particular evaporation flask, for a laboratory device (30), in particular a rotary evaporator, with a vessel body (12) made of glass, which defines a receiving space (17) for a medium to be heated, in particular a liquid, characterized by at least one heating resistance element (20) which is in thermally conductive contact with the vessel body (12) and has a connection (23) for supplying electrical energy, wherein the connection (23) comprises at least two sliding contact surfaces (25) which surround a neck (15) of the flask-shaped glass vessel (12).

The invention belongs to the technical field of chemical analysis and detection. The invention provides a platinum complex fluorescent probe as well as a preparation method and application thereof in detection of water. The chemical formula of the platinum complex fluorescent probe is C23H16ClN3Pt; the preparation method comprises the following steps: 1, under the protection of argon, mixing terpyridine, potassium tetrachloroplatinate, deionized water and dimethyl sulfoxide in a round-bottom flask, heating, stirring, carrying out reflux reaction, cooling to room temperature, adding concentrated hydrochloric acid, carrying out suction filtration to obtain a precipitate, and drying to obtain Pt-Cl; 2, Pt-Cl, phenylacetylene, cuprous iodide, N, N-dimethylformamide and triethylamine are mixed into a round-bottom flask, then argon is pumped and replaced for multiple times, after a reaction, suction filtration is conducted, precipitates are obtained, washing and drying are conducted, and the catalyst is obtained. The platinum complex fluorescent probe is applied to detection of water and has the advantages of specific selectivity, high sensitivity, wide detection concentration range and the like, so that the detection can better meet the current requirements.

The invention discloses an improved method suitable for a'volatile substance molar mass determination 'experiment in a physical and chemical experiment established in a higher school. Comprising the following steps: S1, firstly, lapping a device, and replacing an original Meijoa method steam density measuring device with an improved two-mouth round-bottom flask and a soap film flowmeter; s2, replacing an original three-way piston with a T-shaped pipe; and S3, replacing glass bubbles with a medical injector sample injection mode. Experiment results show that the improved experiment is simple in operation and obvious in phenomenon, experiment cost and uncertainty are reduced, and the method is more suitable for grouping experiments of students.

The utility model discloses a multifunctional chemical experiment device, which belongs to the technical field of teaching aids and comprises a main body, the main body comprises a three-neck cylindrical flat-bottomed flask, a bottle cavity is arranged in the three-neck cylindrical flat-bottomed flask, and three groups of distributed open piles are arranged on the top surface of the three-neck cylindrical flat-bottomed flask. According to the property verification device, experiment operation and teaching processes are carried out through the bottle cavity in the three-neck cylindrical flat-bottomed flask, heating is not needed in the gas preparation process, the acid amount is controlled at any time, the pressure intensity generated by Cl2 can be automatically adjusted through the balloon communicated with the top surface of the three-neck cylindrical flat-bottomed flask, the safety coefficient is high, and the experiment efficiency is high. Redundant Cl2 in the experiment process can be automatically absorbed by soda lime in the balloon and can also be absorbed by injecting a sodium hydroxide solution through the glass charging valve, so that the operation is more convenient, the whole experiment is performed in a sealed environment, the mouth part is polished, the sealing performance is good, the environment is protected, the Cl2 can be effectively prevented from polluting the environment, and the environmental awareness of students is enhanced.

The utility model discloses a multi-isotope purification and separation device which comprises a plurality of transfer cylinders which can be communicated end to end. The multi-isotope purification and separation device further comprises an evaporation assembly, a chromatography assembly and a membrane separation assembly, wherein the evaporation assembly comprises a distillation flask, and a glass guide pipe is arranged at the upper end of the distillation flask; evaporation pipelines are arranged on the distillation flask and are positioned on two sides of the glass guide pipe; the chromatographic assembly comprises a transfer conduit arranged on a transfer cylinder, and a chromatographic column is arranged at the lower end of the transfer conduit; the transfer conduit is divided into two sections, and a filter is connected between the two sections; the membrane separation assembly comprises a transfer conduit II and a filter II which are communicated with a transfer cylinder; a membrane separation pipe is arranged at the lower end of the transfer conduit II. According to the device, different treatments can be carried out on a plurality of isotopes of hydrogen and oxygen elements, a plurality of steps of evaporation, condensation, liquid chromatography, membrane separation and the like are integrated, different pre-treatments can be carried out according to the separation requirements of different isotopes, and the isotope separation efficiency and the operation convenience degree are improved.

The utility model discloses equipment for measuring total phosphate in boiler water and cooling water, and belongs to the technical field of devices for measuring phosphate. A device for measuring total phosphate in boiler water and cooling water comprises a pipette, a colorimetric tube, a spectrophotometer, filter paper and a beaker, and further comprises a water bath kettle used for heating the colorimetric tube; the placing groove is formed in the water bath kettle, and the placing groove is used for placing a colorimetric tube; the plurality of groups of hollowed-out hole baskets are arranged in the placing groove; a filtered sample is directly added into the colorimetric tube, is digested for half an hour in a water bath environment, and then is cooled for colorimetric, so that the risks of breakage and incomplete transfer caused by directly heating a flask with open fire are effectively avoided, the accuracy of an analysis result is ensured, and the threaded column and the jacking ring can be matched with a screw rod, so that the detection accuracy is improved. Furthermore, the position of the colorimetric tube is adjusted, so that the colorimetric tubes with different lengths can be conveniently heated.

Title: Laser marking device, installation and associated method The present invention relates to a device (1) for laser marking containers (2), in particular bottles or flasks made of thermoplastic material, of the type comprising at least one body (23), a shoulder (24) in the extension of said body (23) at an upper end thereof, a neck (21) in the extension of the shoulder (24), and a base (22) at the lower end of said body (23), said device (1) comprising at least: - a plurality of laser marking stations (3), each station (3) comprising along an optical path at least one optical laser marking head (30) equipped with a laser head unit (300) and an optical system (320) for focusing a laser beam (31) in order to generate a mark (310) at the level of at least one marking zone (20) of each container (2) to mark said zone (20),and - control means (4) connected to the marking stations (3) and comprising a laser processing unit (40) and the power supply means (41) for the laser marking stations (3). The device is characterized in that it comprises a carousel (5) with a vertical axis of rotation X driven in rotation by at least one motor relative to a frame (7) via a bearing means (70), said carousel (5) comprising at least: - a first platform (50), said first platform (50) supporting a plurality of retaining members (54) for positioning said container (2) along an axis substantially parallel to the vertical axis of rotation X of said carousel (5),- a barrel (53) supporting the plurality of marking stations (3) such that each optical system (320) is located opposite a container (2) held by a retaining member (54). The present invention also relates to a container marking method and a container marking installation (2). Figure for the abstract: Figure 1,

The invention belongs to the technical field of development and application of water treatment functional materials, and discloses a Fe3O4 / FeS composite modified biochar material with good regeneration performance and preparation and application thereof, and the preparation method comprises the following steps: S1, material pretreatment, S2, biochar preparation, and S3, FeS modified biochar material preparation: sequentially adding FeSO4. 7H2O and biochar into a three-necked flask under the N2 protection condition, continuously stirring, carrying out suction filtration, washing, and drying to obtain the FeS modified biochar material. Slowly adding a Na2S solution, stirring at the rotating speed of 200rpm in the adding process, continuously stirring, and filtering, washing, drying and sieving to obtain FeS-coated BC after the reaction is finished; and S4, preparing the Fe3O4 / FeS composite modified biochar material: sequentially adding FeCl3. 6H2O, FeSO4. 7H2O and citric acid into a three-necked flask under the protection of N2, continuously stirring, slowly adding FeS (at) BC, uniformly stirring and mixing, carrying out constant-temperature water bath, dropwise adding NaOH to adjust the pH value to 10.5, carrying out secondary stirring, aging after the reaction is finished to obtain a black composite material, washing, filtering, carrying out vacuum drying, and sieving to obtain the Fe3O4 / FeS (at) BC. The method has the advantages and effects that the regeneration efficiency is high and stable, and the Mo (VI) adsorption efficiency is high.

The invention discloses a preparation method of functionalized multi-walled carbon nanotubes (MWCNTs)-NH2, which comprises the following steps: respectively adding a certain amount of carboxylated multi-walled carbon nanotubes and concentrated nitric acid into a three-neck flask, carrying out ultrasonic irradiation, continuously stirring and heating for a certain time, cooling to room temperature after the reaction is finished, carrying out suction filtration and washing, and carrying out vacuum drying to obtain purified multi-walled carbon nanotubes (MWCNTs)-COOH; the purified MWCNTs-COOH, distilled water and ethanol are placed in a three-neck flask, after ultrasonic irradiation, an ethanol solution containing APTMS is added, heating reflux is carried out, after the reaction is completed, a product is subjected to suction filtration, washing and vacuum drying, and a functionalized multi-walled carbon nanotube MWCNTs-NH2 is prepared; according to the preparation method, the APTMS is utilized to modify the MWCNTs-COOH, and the aminated multi-walled carbon nanotube with large specific surface area and average pore size, multiple adsorption sites and stronger adsorption effect is prepared.

The utility model relates to the technical field of biochemical experiment instruments, in particular to an adjustable supporting device for biochemical experiments, which comprises a base, the base comprises T-shaped frames, a cross beam is clamped between the T-shaped frames, a plurality of mounting frames are slidably mounted on the cross beam, and a flask frame is fixedly mounted below each mounting frame. The eccentric handle is rotated upwards to drive the pull rod to move downwards, so that the sliding block and the sliding sleeve clamp the cross beam, the installation frame is fixed, the eccentric handle is rotated downwards, locking is relieved, the installation frame can slide along the first guide groove, the fixing mode of the installation frame is simplified, and fixing and unlocking are faster than those of a traditional mode. The flask frame is arranged below the sliding sleeve, so that the flask can move along with the mounting frame, the adjustment is more convenient, and the error probability can be reduced.

The invention discloses a cleaning device for improving the surface modification treatment quality of metal powder and a using method thereof.The device comprises a bottle burning plug, a cleaning rod body, a cleaning block and a side edge cleaning assembly, one end of the cleaning rod body penetrates through the bottle burning plug to be connected, and the other end of the cleaning rod body is connected with the cleaning block; a fixing strip is arranged on the side wall of the cleaning rod body and connected with the side edge cleaning assembly. The cleaning device suitable for cleaning the single-mouth / multi-mouth round-bottom flasks is simple in design structure and free of a mechanical transmission device, and the manufacturing cost can be greatly reduced. The device can achieve automatic and efficient cleaning without manual operation, when the device is used, only the upper portion of the cleaning rod body needs to be connected with the rotating speed regulator, the cleaning rod body can drive the cleaning brush and the cleaning block to continuously sweep while rotating, and therefore all-directional cleaning of the round-bottom flask is achieved. The device further has the advantages of being high in adjustability, good in adaptability and the like, and different types of cleaning requirements can be met.

This utility model discloses a cell culture dish shaking device, relating to the field of cell culture equipment technology. The utility model includes a housing with a tray on top. A locking mechanism is movably connected to the top of the tray, and a shaking mechanism is fixedly connected to the inner cavity of the housing. The locking mechanism of this utility model employs a design of magnetic locking blocks engaging with slots and magnetic adsorption. When replacing the expansion plate, the experimenter only needs to align the magnetic locking block of the expansion plate with the slot on the tray, and installation can be quickly completed using magnetic force, without the need for any tools. Disassembly only requires applying an external force slightly greater than the magnetic force to separate the expansion plate from the tray, significantly saving experimental preparation and cleaning time and improving experimental efficiency. Furthermore, by replacing expansion plates of different specifications and shapes, it can adapt to cell culture dishes of different sizes, as well as diverse experimental containers such as flasks and deep-well plates, greatly enhancing the adaptability of the device to different experimental needs.

The utility model relates to a cyclic lifting device for multi-specification flasks for experiments, which comprises a base, two supporting columns are symmetrically arranged on the base, and the base and the supporting columns jointly form a main frame; chain wheels are symmetrically arranged on the tops and the lower portions of the two supporting columns correspondingly, the two chain wheels located on the upper portion are flush with each other, the two chain wheels located on the lower portion are flush with each other, a chain is connected between the two chain wheels on the same side, and the two chains are symmetrical; a transmission shaft assembly is connected between the two chain wheels located on the lower portion, the transmission shaft assembly is in transmission connection with a driving assembly, and the driving assembly is in communication connection with a control module. A plurality of sliding shaft assemblies are arranged between the two chains, and one or more hook assemblies are connected to the sliding shaft assemblies in a sliding mode.

The utility model relates to the technical field of placing frames, and discloses a stoichiometric instrument placing frame which comprises a supporting frame, the outer portion of the supporting frame is fixedly connected with a supporting plate, the top of a base is fixedly connected with a protection mechanism, the protection mechanism comprises a fixing block, the bottom of the fixing block is fixedly connected to the top of the base, and the bottom of the fixing block is fixedly connected to the top of the base. A protective cover is rotatably connected to the exterior of the fixing block, a glass plate is fixedly connected to the top of the protective cover, a test tube support is slidably connected to the top of the base, and a plurality of test tube bottles are slidably connected to the interior of the test tube support. According to the utility model, a test tube is placed in the test tube bracket and then placed in the protective cover, so that a reagent needing to be observed in the test tube is prevented from being polluted, a plurality of iron rods are further arranged, flasks with different sizes are placed through the iron rings and the flask clamps, the placement is more stable, and the plurality of cooperation is more convenient. The multifunctional effect of the placing frame is achieved.

The utility model relates to a kind of constant temperature systems for epoxidation test application, including water bath, three-necked flask, agitator and cooling assembly;Water bath has a kettle body, the kettle body is a hollow container with upper end opening, still open a drain in the bottom side of kettle body, still set up a liquid level float ball in kettle body;The three-necked flask is placed in kettle body, the three-necked flask has a top and two side ports, one side port is reactant material feeding port, another side port is provided with a thermometer, the agitator has a stirring rod from the top of three-necked flask into the bottle body of three-necked flask, still set up stirring paddle on the top end of stirring rod;Cooling assembly includes a cooling nozzle, the bottom surface of cooling nozzle is opened with several spray ports.The constant temperature system in the utility model, through the intercoordination between water bath, cooling assembly and liquid level float ball, thermometer, to cooperate with controller interlock, the three-necked flask is heated or cooled, to realize the constant temperature of three-necked flask provides good foundation.

The utility model discloses a protection device for measuring ferrous iron in iron ore, and relates to the technical field of experimental instruments, the protection device comprises a base, a plurality of first grooves are formed in the right side of the top end of the base, and a heating assembly is arranged in each first groove; a flask is placed in the first groove and located on one side of the heating assembly, and a position adjusting assembly is fixedly connected to the base and located on one side of the flask. By the adoption of the structure, the first groove is formed in the base, the bottom of the flask is inserted into the first groove, then the grid plate is driven by the position adjusting assembly to move, and the positioning assembly in the through hole of the grid plate makes contact with the flask, so that the position of the flask can be stabilized, the conical flask is better fixed, and the conical flask is prevented from shaking or toppling over; the stability and the safety of experimental operation are improved, and reliable guarantee is provided for a ferrous iron determination experiment.

The invention discloses a construction method of NMN fermentation accumulation engineering bacteria, which comprises the following steps: by using FastPfu Fly high-fidelity enzyme as an enzyme kit for amplification, and by using a DNA fragment containing a target fragment or plasmid or genome as a template, carrying out amplification on the NMN fermentation accumulation engineering bacteria to obtain the NMN fermentation accumulation engineering bacteria. 3-5 [mu] L of a PCR product is sucked for nucleic acid gel electrophoresis to detect whether the size of a band of a target gene is correct, a recovered DNA fragment and a vector are subjected to seamless cloning or CPEC connection, the connected DNA is transferred into competent cells through an electrotransfection or chemical transfection method, and the target gene is obtained. After incubating, coating to a corresponding resistant plate for culturing until a single colony appears; carrying out plasmid extraction on the obtained bacterial liquid by using an AxyPrep plasmid small extraction kit; preparing an electro-competent state; the E.coli gene is knocked out based on a two-step method of a Cas9 recombination system; shaking a fermentation engineering strain laboratory flask and a fermentation tank; and detecting a fermentation product.

The utility model belongs to the technical field of constructional engineering, and discloses a silicon-hydrogen content testing device which comprises a magnetic stirrer, a reaction mechanism is arranged at the top end of the magnetic stirrer, and the reaction mechanism is attached to the top end of the magnetic stirrer; the reaction mechanism comprises a pear-shaped flask, a magnetic stirrer in the magnetic stirrer is located at the bottom end of the inner wall of the pear-shaped flask, the top end of the pear-shaped flask is communicated with a constant-pressure dropping funnel, the tail ends of the silicone tubes are communicated with a gas sampling measuring tube, and the tail ends of the other group of silicone tubes are communicated with a leveling bottle. According to the utility model, gas is released through the reaction of an object to be measured and alkali liquor, water is pressed into the gas measuring pipe, the volume of the released gas can be measured through the liquid level difference of two times, and the content of silicon and hydrogen in the object to be measured can be calculated. Therefore, the detection data can be more intuitively recorded, the accuracy of the data in the detection process is guaranteed, and the chemical reaction is more sufficient in the chemical reaction process.