65 results about "Centimeter" patented technology

The invention discloses a delaunay-triangulation-network-based multi-redundancy network RTK atmospheric error interpolation method. A network RTK data processing center constructs a Delaunay triangulation network based on a correct coordinate of a CORS base station; after a user is accessed to a data processing center, an optimal triangular unit and a suboptimum triangular unit of the location of the user are selected; an atmospheric error interpolation base line number is extended; an MLIM ionized layer interpolation model and an RELIM tropospheric interpolation model are established; and an atmospheric interpolation completeness monitoring method of a moving station in a grid is provided. The interpolation precision of the MLIM ionized layer interpolation model is higher than that of the traditional model by three times and the interpolation precision of the RELIM tropospheric interpolation model is higher than that of the traditional model by 6 to 30 times; and the two models can still have high interpolation precision at an area with a large elevation difference at the base station. A regional CORS ionized layer and tropospheric completeness index can reach a centimetre-level interpolation precision, so that real-time positioning completeness monitoring of a network RTK user can be realized. With the method provided by the invention, a CORS base station around a user can be utilized fully; the atmospheric delay interpolation precision of the area can be improved; and the rapid and high-precision positioning of the user can be guaranteed.

The invention discloses a repair method for mercury-polluted soil. The repair method comprises the following steps: ploughing up surface soil with a depth of 25-30 centimetres away from ground surface, of the mercury-polluted soil, air-drying, grinding and sieving to obtain pre-treated surface soil; forming a passivator from 40-55 parts of bentonite, 5-15 parts of hydroxyapatite, 3-8 parts of ammonium thiosulphate and 8-16 parts of calcium hydroxide in parts by mass; adequately and uniformly mixing the passivator with the treated surface soil according to an added amount which is 2-5% of the mass of the surface soil, of the passivator, standing for 10-20 days until mercury with a content of 70% in the surface soil is fixed, and completing passivator repair; and levelling the surface soil, planting Indian mustard, dissolving calcium thiocyanate in water and uniformly spraying the solution into the peripheral soil of the root systems of Indian mustard during the vigorous growth period of Indian mustard, and finally harvesting Indian mustard. The repair method disclosed by the invention is simple to operate, low in cost, short in remediation period, and suitable for application of repair for large-area mercury-polluted soil plants.

The invention discloses an infrared nondestructive testing and imaging method based on an array laser source and used for structure surface cracks. The method comprises the following steps: expanding the beam of a laser source generated by a pulse laser device into a collimation laser beam with the diameter of several centimetres by virtue of a laser beam expander at first, and then focusing the laser beam onto the surface of the tested piece by virtue of m*n array convex lenses to form array laser spots with radiuses of less than 1mm and uniformly distributed, and then monitoring the temperature field distribution change condition of the surface of the tested piece irradiated by the array pulse laser source by using an infrared camera; when cracks exist in the irradiated area of the surface of the tested piece, the cracks block the diffusion of the heat of the laser irradiation on the surface, thus forming a high temperature difference at the both sides of each crack. Therefore, the cracks on the surface of the tested piece can be tested and imaged through the temperature gradient field of the irradiated area. The method disclosed by the invention has the advantages of being simple in system structure, easy to realize and operate, high in testing speed, high in sensitivity, intuitive in result, capable of realizing remote testing, and the like.

The invention provides an RTK measuring receiver tilt measurement method. The method comprises the following steps that 1, the bottom of a centering rod is fixed, tilting and shaking are conducted, and then measurement is conducted; 2, on the basis of the above-mentioned measurement, a measurement point sequence, a measurement point tilted sequence, a measuring rod length and an antenna phase center height are obtained; 3, on the basis of a numerical value obtained through measurement, a positioning quality target and geodetic coordinates of the points to be measured are obtained; 4, whether the positioning quality target meets the requirement or not is judged, weather measurement is finished or not is determined. According to the method, the positions of the points to be measured are calculated according to the positions and inclination angles of the receiver antenna phase center, the centering rod length and the like when a certain number of tilt measurements are conducted, and for centimetre-sized RTK, when the number of observed values is enough, the centimetre-sized position calculation precision can be obtained.

The invention provides a precise positioning and ranging method for a suspended track unmanned vehicle based on UWB and DGPS technologies. The precise positioning and ranging method comprises the steps that: a DGPS and a UWB positioning and ranging system are installed on the unmanned vehicle; both the DGPS and the UWB positioning and ranging system are connected with a vehicular control system; the vehicular control system performs positioning, ranging and unmanned driving of the vehicle through the DGPS and the UWB positioning and ranging system; a vehicular GPS and a base station form the DGPS; UWB sensors of front and rear vehicles on the same track form the UWB positioning and ranging system; mutual electromagnetic pulse signals are sent; the distance between the front and rear vehicles is obtained through a TOF algorithm; and, as the supplement of the DGPS, when the GPS does not have a satellite signal, the unmanned driving security of the vehicle is ensured through the wirelessranging of the UWB between the vehicles. According to the precise positioning and ranging method provided by the invention, the UWB and DGPS positioning technologies are applied to control of the suspended unmanned vehicle at the first time; the disadvantage that the GPS cannot complete positioning in some cases can be made up by the UWB technology; and thus, the positioning and ranging precisionis up to the centimetre level.

The invention discloses a land piling system and method precisely guiding a driver to look for piling points. The method comprises the steps: importing coordinates: importing designed pile site coordinates and elevations; selecting points in a plane; selecting the piling point this time; looking for the point in the plane: moving a piling trolley according to direction prompt information and micro-turning a piling hammer; piling depth control: prompting to control pile stop according to a residual hamming distance; and exporting a report form: exporting time, coordinate, pile height data. The invention discloses the land piling system precisely guiding driver to look for piling points as well. A high-precision positioning GNSS positioner product designed for conditions of a severe construction environment and strong vibration of engineering machinery, the high-precision positioning GNSS positioner product supporting Beidou satisfies centimetre-level high-precision positioning requirements of machinery such as mining machinery, earthwork machinery, construction positioning machinery, piling machinery, transporting machinery, locomotives and the like. The product is the first mechanical positioner at home and is high in reliability.

The invention discloses a movable lotus root-cultivating pool as well as a method and a tool thereof, belonging to a cultivating and breeding system. A whole piece of waterproof cloth is laid on the whole bottom and the enclosure of the pool. The invention is characterized in that the outer sides of piles (13) fixed on a foundation are connected with the waterproof cloth (1) through a special tool so as to serve as a pool dam, and the waterproof cloth (1) is extended by cloth-connecting clamps (6) and is supported by cloth-supporting clamps (8); and the joint parts (15) of the pile (13), the waterproof cloth (1) and the foundation are provided with connecting mechanisms, and a drain valve (17) and a feed valve (18) are arranged in the pool. The invention has the advantages of leaking stoppage, water level regulation, no pollution and reduced cost; and the effect can be better if the tilled land and wasteland of paddy fields as well as the ceilings and cement foundations of urban tall buildings are utilized. The method comprises the following steps: laying 15-20 centimetres of soil by utilizing the special tool; transporting up and down in a building; plowing and weeding; ditching; burying lotus roots; and harvesting, wherein water the height of which is 20 centimetres is introduced in the pool, so that the lotus roots can grow in the shallow soil layer plane in all directions, thus the lotus roots can be harvested easily, especially the acre yield is increased to 12000 jin from more than 1000 jin, and simultaneously the invention has the advantages of purifying air, regulating air temperature, beautifying cities and the like.

The invention discloses a method for producing pine needle health protection tea, which chooses one kind of pine needle selected from the group consisting of Chinese pine, Chinese red pine and Japanese red pine of over six years old and 3m high. The preparation method comprises the following steps: picking pine needles on any of non-polluted Chinese pine, Chinese red pine or Japanese red pine of over six years old, three meter high; taking out the impurities in the pine needles and rinsing the pine needles with clean water; placing the needles in 3-5% salt water and soaking for 25-30 minutes; taking out the soaked pine needles to rinse with clean water and dry, cutting the pine needles into 0.5 centimetre long for later use, rinsing medlar with clean water and drying for later use; putting the processed pine needles into a fried tea machine to fry and placing the fried pine needles in a ventilated area to cool; finally, putting the processed pine needles, wolfberry and rock sugar into the tea bag in proportion and finishing the sterilization packaging. When the tea is brewed by 100 DEG C boiling water, the nutrients are released quickly and absorbed easily by human body, thereby achieving anti-aging purposes and physical fitness.

The invention relates to a method for conveniently and fast observing stem tip flower bud differentiation of tobacco plant, belonging to the technical field of developmental biology of plants. The method comprises the following steps: a. taking a sample with a blade at the position which is 5 centimetres downward from the stem tip; b. after sampling, immediately placing the stem tip in an ordinary injector for medical use, which has a volume of more than 15mL, pushing a pushing rod of the injector to the bottom, using a thumb to block the front part of a needle tube and forcefully pulling up the pushing rod to the top of the injector; retaining the position for 1-3min and repeating the process for 3-4 times; c. fixing the stem tip sample in a stationery liquid for 24h for testing with components having the following proportioning: 5.0mL of formaldehyde with a concentration of 38%, 5.0mL of acetic acid, 90.0mL of alcohol with a concentration of 75%; d. using a stereomicroscope to observe and take photos of the sample. The method has the advantages of low cost, simple and convenient operation, fast observation and acquisition of digitalized pictures with clear images, thus being of great guiding significance for experimental studies.

The invention relates to a preparation technology of a centimetre wave-millimeter wave compatible absorbing material. The material is of five-layer structure, and a substrate is an irregular surface made of any material; the topmost layer is a first layer, and mainly consists of a W-shaped hexagonal ferrite absorbing agent and an acrylic resin adhesive; a second layer is composed of a carbonyl iron powder absorbing agent and an epoxy resin adhesive, and a third layer is composed of a Fe85Si1Al6Cr8 nanometer crystal thin absorbing agent and an epoxy resin adhesive; a fourth layer is composed of a polycrystal iron fibre absorbing agent and an epoxy resin adhesive; and a fifth layer is composed of a chopped carbon fiber, a sooty mixed absorbing agent and a polyurethane adhesive. A preparation process comprises the following steps: firstly, covering and preparing a bottom fifth-layer medium coating on the substrate; and then successively covering and preparing a fourth-layer medium coating, a third-layer medium coating, a second-layer medium coating and a first-layer medium coating, wherein the coating preparation of each medium coating is as follows: uniformly stirring a coupling agent, a diluting agent and the absorbing agent of each layer, standing, then adding the adhesive of each layer, uniformly stirring to obtain a paint, coating the paint, and curing, thus obtaining the centimetre wave-millimeter wave compatible absorbing material.

The invention discloses a sewage treating agent and a preparation method thereof. The sewage treating agent comprises the following raw materials in parts by weight: 18-22 parts of corn straw, 4-5 parts of cassava dregs, 7-9 parts of a starch derivative, 6-8 parts of polyacrylamide, 10-12 parts of polyferric sulfate, and 14-17 parts of diatomite; the preparation method comprises the following steps: corn straw whose water content is 60-70% is crushed into segments of 1 centimetre, the corn straw, the cassava dregs, polyacrylamide, and polyferric sulfate are uniformly mixed and placed into an ensilage trough, compacting is carried out, a plastic film is covered, fermentation is carried out for 4-6 days at 20-30 DEG C, in order to obtain fermented straw; the fermented straw, the starch derivative, and diatomite are uniformly mixed, in order to obtain the sewage treating agent. The sewage treating agent can be used for effectively removing various pollutants in the sewage, and especiallyhas substantial effects for treatment of dye waste water.

The invention discloses a multiposition microwave reactor with a reflection cavity. The multiposition microwave reactor comprises the reflection cavity, a reactor subassembly and a microwave radiatorsubassembly and is characterized in that the reflection cavity is a tubular shell which is made of a microwave reaction material and has the cross section being square; microwave reaction bodies are arranged at the four corners of the tubular shell respectively; the reactor subassembly comprises four tubular reactors which are arranged side by side and have the cross sections being square; a diagonal line of the square cross section of the reactor subassembly and a diagonal line of the cross section of the reflection cavity are arranged in the tubular shell in a mutual perpendicular manner; the microwave radiator subassembly comprises a microwave radiation head and a microwave source; the radiation head is a rod-like slot antenna radiator; the radiation end of the radiation head is arranged in a center line of the tubular shell; and a connector end of the radiation head is exposed out of the tubular shell and is connected with the microwave source through a coaxial cable. The inventionadopts an absorption and reflection energy feedback device, by arranging a reflection cavity body, the microwave utilization ratio is obviously increased; the absorption and reflection energy feedback device is small in size reaching a centimetre level and can conveniently perform microwave treatment on multiple trace or a small amount of samples at the same time.

The invention discloses a non-crystal alloy of centimetre grade plastic Cu-(Zr, Ti)-Al system block, which possesses 50-100% non-crystal phase, wherein the structural formula of system alloy is Cu45Zr48-xAl7Tix (x is atom percentage of Ti element, which is between 0.5 and 6).

The invention discloses a beta-graphite diyne nano-film as well as a preparation method and application thereof. The method comprises the following steps: taking copper foil or any substrate covered with copper foil on the surface as a substrate and performing a coupling reaction on tetra-alkynyl ethylene and diamines compounds in a solvent, so as to obtain the beta-graphite diyne nano-film after the reaction is finished. In the method, the optimally improved Glaser-Hay coupling reaction is adopted, so that the process is simple and convenient, and the centimetre-level beta-graphite diyne nano-film can be prepared on the surface of the copper foil substrate on a large scale; the film is stable in property and continuous and uniform in surface; the conductivity can reach 3.47*10<-6>S.m<-1>; the film is a two-dimensional carbon nanomaterial with a novel electronic structure and has potential application prospect in the fields of catalytic materials, electronic devices, catalysis, materials and the like.

The invention discloses a method for releasing dormancy of oil-used peony seeds. The method comprises the following steps: a quick post-maturation stage of seed embryos of the oil-used peony seeds: harvesting peony pods, spreading the peony pods in shade indoors, and overturning up and down once very day; after the pods crack naturally, screening and collecting shed seeds; performing stratification treatment after full seeds which submerge in water are dried in shade indoors for 1 to 2 days; adding fresh river sand which contains 50 to 60 mass percent of water in the screened seeds, and spreading a mixture indoors for drying; keeping internal temperature and humidity of a mixture of the seeds and the river sand, and treating for 30 days to obtain the mixture of the seeds with the seed embryos which are completely matured and the river sand; a hypocotyledonary axis dormancy releasing stage of the oil-used peony seeds: controlling the indoor temperature of the mixture of the seeds and the river sand to be between 15 and 20 DEG C, keeping the humidity of the river sand, and treating for 30 days to obtain a mixture of the seeds of which the root length is greater than 4 centimetres and the river sand; an epicotyl dormancy releasing stage of the oil-used peony seeds: controlling the indoor temperature of the mixture of the seeds of which the root length is greater than 4 centimetres and the river sand to be below 10 DEG C; spraying a plant growth conditioning agent; keeping the river sand at a certain humidity; treating for 30 days; completing a dormancy releasing process of the oil-used peony seeds.

An optical cable includes an optical core and an external sheath surrounding the optical core. The external sheath includes a first material having a first, higher fracture toughness and a second material having a second, lower fracture toughness. The first and second materials are arranged so that the second, lower fracture toughness material is accessible from outside the cable along at least one longitudinally extending area of the sheath outer surface. For accessing the optical core of the cable, a short longitudinal cut, namely, few centimetres, is made with a blade in the accessible second, lower fracture toughness material. Then, its cut edges are pulled apart by hand. The pulling force causes the lower fracture toughness material to fracture, thereby propagating the initial short cut longitudinally along the sheath through its whole thickness.

A bed assembly (10) includes a wheeled base (12), a sub-frame (16) and mattress support frame (18). The sub-frame (16) supports a plurality of electrically operated actuators which provide for raising and lowering of the bed (10). The bed can be lowered to a first low position in which the bed frame (18) is around 38 to 45 centimetres above floor height and to a lower position in which the frame (18) is around 30 centimetres above floor height. The bed is lowered to the first height upon receipt of a first command input and can only be lowered below that first height upon receipt of a second control input distinct from the first control input. Preferably, the bed is lowered at a slower speed from the first low height to its lowermost position.

The invention relates to a tight reservoir millimeter-level sample oil source direct analysis and comparison method. The method includes the following steps that: a borehole rock core is treated according to a non-conventional tight and mud shale rock core lithology fine and accurate description method, so that a tight reservoir rock core lithology description result is obtained; the rock core isfrozen and then is cut according to the obtained tight reservoir rock core lithology description result, and a frozen rock core sample is obtained; the centimetre-level or millimeter-level stripes ofthe tight reservoir and source-reservoir micro-combination of the sample are drilled so as to be sampled, and an obtained sample is packaged, and then is frozen and stored; a milligram-level sample from the frozen and stored sample is weighed, and is arranged in the heat-release tube of a tight reservoir oil source direct analysis and comparison system, after heat release is performed, a tight reservoir and source-reservoir micro-combination rock hydrocarbon fingerprint analysis spectrogram and data are obtained, and analysis data processing is carried out, and hydrocarbon fingerprint analysisgeological experiment parameters and fingerprint ratio parameters are obtained; and non-conventional tight oil and mud shale oil source-reservoir micro-combination oil source comparison and oilinessevaluation are carried out on the basis of the geological experiment parameters and the fingerprint ratio parameters.

The invention discloses vegetable crisp chips as well as a preparation method thereof. The method comprises the following steps: vegetables which are pretreated are soaked into clear water whose volume is 2-4 times the volume of the pretreated vegetables for 30-40 minutes; soaked vegetables are taken out and washed with clear water till the vegetables are clean; the cleaned vegetables are placed into a boiling device for boiling till the vegetables are medium to medium well boiled; boiled vegetables are cut into pieces whose lengths are from 2 centimetres to 4 centimetres, and the cut vegetables and flavour liquid are placed into a beater according to a predetermined weight ratio and beaten into a pulp; the pulp is placed into a vegetable crisp chip mould, and the mould is sent into a quick-freezing device for quickly freezing the mould for 45-120 minutes; the quick-frozen mould is sent into a microwave drying machine, drying, sterilizing and crisping treatment is carried out for 100-120 minutes within a temperature range from 35 to 65 DEG C under the pressure from 0.09 to 0.1Mpa. The vegetable crisp chips can satisfy people who like to eat puffed food, and provide abundant nutrition for people at the same time.

A lace (200) for a shoe (C), consisting of an elongate elastic band (2) made entirely of silicone, said band having elastic properties according to which, when at least one segment of said band is selected, said segment having a constant cross-section and a rest length of 5.0 centimetres, when said segment is stretched to a stretched length of 10.0 centimetres and then released, said segment contracts and reaches a first released length of between 5.6 and 7.0 centimetres after a first period of between 0.1 and 1 second after the release, and reaches a second released length of between 5.0 and 5.6 centimetres after a second period of between 15 and 25 seconds after the release. The invention is particularly applicable in the field of sports shoes, and in particular running shoes, to prevent any compression and thus allow good blood circulation while holding the foot comfortably.

The one-piece board of the invention relates to a heat preservation decorative material for building external walls. The one-piece board of the invention is composed of an ultrathin natural stone with a thickness of 7+ / -1 mm and a hard bubble polyurethane thermal insulation material, and the periphery and the back side of the one-piece board are packed by a high pressure cement fibrolite plate serving as a fireproof frame. Firstly, natural stone is processed into the ultrathin natural stone with a thickness of 7+ / -1 mm, a dovetail groove is arranged at the back of the ultrathin stone and one centimetre-width thicknessing processing is carried out at the periphery of the back of the ultrathin stone to facilitate the installation of the fireproof frame; and then, the high pressure cement fibrolite plate and the ultrathin stone are put into a prefabricated mould and the polyurethane serving as the thermal insulation material is injected into the mould by a machine. In the invention, the stone with a thickness of 7+ / -1 mm is adopted to solve the problem that the traditional hang stone with a thickness of 2.5 centimetres bears the weight of the wall; in addition, the one-piece board integrates fire proofing and decoration, and a decorative surface is completed by one-off construction, which accelerates on-site construction speed and construction security; each piece of the thermal insulation material is a totally-enclosed independent whole, so that the thermal insulation material is more durable.

The invention relates to a method for preparing a food, in particular to a method for preparing Chinese sauerkraut. Pickling materials comprise the following raw materials in parts by weight: 70-100 parts of potherb mustard, 5-10 parts of wild pepper, 20-50 parts of aniseed, 1-5 parts of cinnamon and 1-5 parts of anisum fruit. The preparation method comprises the following steps: 1, washing and chopping the potherb mustard; 2, placing the wild pepper, aniseed, cinnamon and anisum fruit which are wrapped into a yarn bag, placing the yarn bag in water, boiling on fire for 15-20 minutes, and taking out the yarn bag for spare use; 3, throwing the potherb mustard into a container until the potherb mustard piled in the container is 5-10 centimetres away from the mouth of the container, and pouring the hot water after the wild pepper, aniseed, cinnamon and anisum fruit are boiled into the container until the hot water is 1-2 centimetres higher than the potherb mustard; and 4, sealing the container, and placing the container at the ambient temperature of 20-28 DEG C for 3-10 days, thus the Chinese sauerkraut is obtained. The Chinese sauerkraut prepared by the invention is delicious and flavourful.

The invention provides a navigation testing method and system simulating walking inertia free of a satellite signal. Testing equipment and high-precision positioning equipment are in a wide environment. The high-precision positioning equipment acquires carrier phase information of a GNSS signal. Carrier phase information of a nearby positioning service supplier CORS is acquired through a RTK account number of the positioning service supplier; a centimetre-level RTK fixed solution is calculated by means of an algorithm, and meanwhile, a result document with corresponding coordinate informationis generated; walking inertial navigation of the testing equipment is initialized after walking for a period of time, and a GNSS signal source of the testing equipment is isolated, so that the testingequipment enters a pure walking inertial navigation working mode and meanwhile, the high-precision positioning equipment further acquires centimetre-scaled RTK fixed solution walking result document,and the walking result document, with coordinates, of the testing equipment and the positioning result document of the high-precision positioning equipment are compared to obtain accurate error statistics. The positioning result of the testing equipment is more accurate.

The invention relates to a fertilizer specially for increasing the yield of grapes, comprising the following raw materials in percentage by weight: 18%-37% of bran, 8%-16% of sorghum flour, 16%-25% of potassic fertilizers, 10%-16% of phosphatic fertilizers, 6%-10% of nitrogenous fertilizers, 4%-9% of calcium fertilizers, 4%-9% of calcium superphosphate, 1%-2% of auxins, 0.5%-1% of lime, 1%-2% of brown sugar, %-2% of dimethoate and 0.5%-1% of dipterex. The fertilizer is prepared through the following steps of: mixing and placing all the 9 raw materials into a stirrer for stirring for 80 minutes according to a proportion, and then taking out; adding the brown sugar, the dimethoate and the dipterex, and uniformly stirring; placing into the stirrer again for stirring for 40 minutes, and then taking out; and molding cylindrical fertilizer columns specially for increasing the yield of the grapes and with the weight of 200 grams, the height of 10 centimetres and the width of 8 centimetres by using a molding machine, wherein the required molded fertilizer columns specially for increasing the yield of the grapes are desirable to be compacted, tamped and difficult to smash when held by hands.

The invention discloses a tubing rounded cover structure of an air-condition, which comprises a rounded ring cover, and the rounded ring cover is composed of a rounded ring which is parallel with the wall and a circular tube wall which is perpendicular and integrated with an inner ring of the rounded ring. An axial direction perforation kerf port is arranged on the rounded ring and the circular tube wall. The width of the rounded ring which is parallel with the wall is from three to six centimetres, and the length of the circular tube wall is from three to ten centimetres, and the diameter of the circular tube wall is from three to six centimetres. The utility model has the advantages of simple installation, extremely low scrappage rate in the process of the installation and low cost.

The invention discloses a portable surface runoff simulating and measuring device. The device comprises a measuring cylinder, a water diversion channel, a runoff frame and a sampling bottle, wherein the measuring cylinder is fixed on a bracket; a water outlet and a valve are arranged at the lower end of the measuring cylinder; the water outlet is communicated with the water diversion channel through a water delivery pipe; a water outlet slot hole is laterally formed in the side wall of the water diversion channel; a supporting seat and an access board are arranged below the water diversion channel; the runoff frame comprises a front inserting plate, a rear inserting plate and two side inserting plates which are connected with one another and form a rectangle; the access board is buckled on the inner side of the front inserting plate through an inserting slit; a runoff output connector is arranged in the outer side of the rear inserting plate; the sampling bottle is communicated with the runoff output connector on the rear inserting plate through a runoff output pipe; a volume scale line is arranged on the side wall of the sampling bottle; a vertical angle measuring device is arranged on the outer side wall of each side inserting plate; a horizontal reference device is arranged on the outer side wall of the rear inserting plate. The simulating and measuring device is centimetre-level in dimension, can repeatedly measuring surface runoff sample data in quantity, and improves the accuracy of observation data.

The general field of the invention is that of visualisation systems intended to be worn on the head of a user wearing an audio headset (30) consisting of a first arch (31) and two side earpieces (32),the visualisation system comprising at least one headband (10) in the form of a strap and a visualisation device (20) mounted on the headband. The headband according to the invention comprises two symmetric side hasps (12D, 12G), each hasp being in the form of an arch, in a manner that provides an opening (13G, 13D) of several centimetres between the arch and the head of the user, in such a way that when the system is worn on the head, the opening is sufficient to allow the passage of one of the two lateral arms of the first arch.

The invention relates to a preparation method for a polymer film for food contact, and particularly relates to a preparation method for a film for a migration test in a food contact material migration model. Polymer grains and a to-be-detected migration object are added in an organic solvent in a certain ratio, and adequately dissolved to form a mixed solution with viscosity; a certain amount of the mixed solution is taken, and dripped on a polymer composite isolation pad with the diameter of 2-5 centimetres, or the polymer composite isolation pad is placed in a spin coater, the mixed solution is added in the spin coater, and the spin coater is started. The polymer composite isolation pad dripped or sprayed with the mixed solution on the surface is placed in an atmospheric environment, and after the organic solvent in the mixed solution is volatilized, the polymer film containing the to-be-detected migration object is formed on the polymer composite isolation pad. Different from blowing moulding, calendering moulding, tape-casting moulding or stretching moulding for a polymer film, the preparation method disclosed by the invention has the advantages that preparation for the polymer film can be finished on a substrate with small dimensions, and moreover, the thickness of the obtained polymer film and the content distribution of the to-be-detected migration object are uniform, thus laying the foundation of a parallel test in the further migration test.