542 results about "Freeze and thaw" patented technology

A mold is disclosed for forming a freezable and thawable bag of uniform thickness, especially useful for cryopreservation of thermolabile substances. The mold features one or more recessed planar surfaces, including radiused peripheral walls about the recesses, a planar top surface, and means for conforming a blank sheet to the mold. Two mold halves combine to form a completed bag. The mold halves may be complimentary.

A bag, method of manufacture and process are disclosed for the cryopreservation of thermolabile substances. The bag is characterized as having substantially uniform thickness throughout its length and height. The bag features a radiused peripheral edge wall for stress relief and to provide the constant cross-section. A peripheral flashing circumscribes the radiused edge wall and provides a suitable purchase area for sealing so that the thus formed bag is less susceptible to fracture particularly when exposed to cryogenic temperatures. The uniform thickness of the bag promulgates uniform heat transfer to and from the contents of the bag in relation to any surrounding medium at a different temperature. The bag affords more space for efficient storage and reduces heat invasion into the contents of the bag when a plurality of bags are placed with their larger planar surfaces in contact with each other.

The invention pertains to pharmaceutical compositions of Zosyn® piperacillin with tazobactam in the presence of a buffer, preferably citrate, a particulate formation inhibitor, preferably EDTA optionally an aminoglycoside which when frozen and thawed or lyophilized and reconstituted reform a solution which has decreased particulate formation.

The present invention provides an energy storage device that utilizes a cold sink that undergoes cycles of freezing and thawing. The device converts electrical energy to stored thermal energy, and then re-converts the stored thermal energy to electrical energy, as needed or desired. The device can store energy on a large scale (e.g., on the order of megawatts or greater) and for an extended period of time (e.g., for at least 12 hours, or longer, as needed).

A method for making, storing and using a surgical graft from equine amniotic membrane in veterinary ophthalmology. The amniotic membrane is obtained from equine placenta, from which the chorion has been separated. Sheets of the amniotic membrane are cut to size and mounted on filter paper. The cells of the amniotic membrane are killed, preferably while being frozen and thawed in the storage solution. The equine amniotic membrane can be used in a variety of ocular surgeries in horses but also other species such as food animals, dogs and cats. It represents a strong biomaterial that will give a good physical support to the ocular tissues while inducing a minimal amount of scarring which is primordial in ocular surgeries in order to obtain the best visual outcome.

The invention provides a sterile polymerized covering for a wound surface-medical wet dressing for a burn wound, a preparation method of the dressing, and application. The dressing comprises the following components: 10 to 30g of chitosan, 30 to 80g of polyving akohol, 5 to 10g of alginate, 5 to 15g of isomaltose hypgather, 2 to 6g of carbomer 940, 2 to 5g of gelatin, 5 to 10g of sodium carboxymethylcellulose, 10 to 30g of glycerol, and 0.01 to 0.2g of menthol; 15 to 60g of condensed tannin which is remarkable in treatment can be selectively added; and a skin penetration enhancer or an appearance conditioning agent also can be selectively added. The dressing can be prepared into an irregular dressing in order to be suitable for the wound surfaces in irregular and special positions and also can be prepared into a solid plate-shaped dressing which can be shorn at random. According to the sterile polymerized covering dressing for the wound surface, the freezing and thawing technology and the irradiating technology are combined and cross-linked to realize the preparation, and the defects of the prior art can be overcome. The dressing is high in biocompatibility, free from toxicity and sensitization and high in mechanical strength and comfort level, is out of adhering during the process of being replaced after being attached for a long time, and is a nonantigenic protective barrier which has the effect of resisting and inhibiting bacteria.

The invention discloses a technique for extracting phycocyanin, chlorophyll and spirulina polysaccharide in spirulina, comprising the following steps: taking and weighing fresh spirulina, centrifuging and washing the spirulina, weighing spirulina clay, adding water into the supernatant, stirring evenly, and freezing and thawing twice to break the cell wall, after the second dissolving, adding water, placing for 2-8 hours, centrifuging to obtain supernatant and sediment A, extracting the sediment A by a Soxhlet extracted method with ethanol to divide the sediment A into extraction and sediment B, wherein the supernatant is used for extracting phycocyanin, the sediment A is used for extracting sodium zinc chlorophyllin and the sediment B is used for extracting spirulina polysaccharide. The extraction technique extracts the active substances such as phycocyanin, chlorophyll and spirulina polysaccharide, and fully and effectively utilizes the prior spirulina resource and avoids the resource waste.

The invention relates to anti-cracking alkali exciting ecological cement, which consists of A, B and C, and solid-phase mass ratio of the A to the B to the C is 5-10:75-90:5-15. The A is exciting agent, which comprises the following components by mass percentage: more than or equal to 80 percent of water glass of which modulus is 0.7 to 1.4, and less than or equal to 20 percent of one or a plurality of sodium sulfate, sodium phosphate, sodium carbonate, sodium chloride and magnesium chloride; and the A is prepared into solution containing more than or equal to 40 percent of solid for use. The B is a mineral additive, which comprises the following components by mass percentage: 30 to 70 percent of slag powder, and 30 to 70 percent of other additives, wherein the other additives comprise one or a plurality of siliceous dust, coal ash, metakaolin, red mud, burnt shale, colliery waste, steel slag and alloy slag, and is grinded to powder of which specific surface is 350 to 800m<2>/g. The C is active magnesium oxide, wherein mass content of MgO is more than or equal to 70 percent. The active magnesium oxide is calcined at a temperature of between 700 and 1,000 DEG C and then mixed and grinded with the B to become powder. The cement is the low-carbon discharge ecological cement with the advantages of high-early strength, durability, permeability resistance, corrosion resistance, freezing and thawing resistance, low heat of hydration, good cracking resistance, economy and environmental protection, and is used for civil construction, water conservancy, national defense, and oil well and mine passage support engineering.

The invention relates to a method for freezing and thawing placental whole cells and separating and expanding stem cells. The method comprises the steps as follows: disinfecting and washing a placenta tissue; cutting off placental lobules from the tissue, and carrying out digestive treatment for 20 min; preparing a placenta tissue freezing solution for standby application; adding whole cells obtained by digestive treatment and the freezing solution into a freezing tube, refrigerating for 0.5 h at the temperature of 4 DEG C, freezing for 1 day at the temperature of subzero 80 DEG C, and freezing in liquid nitrogen for standby application; taking out the placental whole cells from the liquid nitrogen when needed, thawing in a thermostatic water bath, carrying out drop-method washing by a culture medium for mesenchymal stem cells, removing red cells by a red cell lysis solution, and expanding the mesenchymal stem cells by the thawed placental whole cells through cell culture and cell passage. According to the method, the frozen placenta tissue can be effectively protected and is convenient to thaw and use; and the method is in particular suitable for separating and expanding the mesenchymal stem cells after thawing the frozen placental tissue.

A freezing and thawing apparatus includes a freezing and thawing treatment tank for filling freezing and thawing treated water, a plurality of ultrasonic vibrators for oscillating ultrasound different in frequency in the freezing and thawing treatment tank, a treated water cooler for cooling the freezing and thawing treated water, and an ultrasonic vibrator controller for controlling the ultrasonic vibrators.

The invention relates to a water-soluble non-combustible ceramic anti-radiation coating and a preparation method thereof. The coating comprises an active material, an inorganic filler, a shrinkage reducing agent, a thickening agent, a flame retardant, a silicate binder, a reflection reinforcing agent and an aid in a mass ratio of (2-2.8):(0.5-1):0.40:(0.01-0.04):(0.4-0.8):2.13:(0.067-0.2):0.3. The coating is formed by fully mixing the components uniformly and can be used for painting or spraying, and a layer of modified fluoro-silicone emulsion is painted on the surface of the coating after the coating is surface-dried. The coating can be used as an exterior wall coating (base coat), and also can be used as a protective coating for the surfaces of an exterior wall thermal insulation plate, mortar, a sintered brick and a building enclosure structure; and the water-soluble ceramic coating has the characteristics of high durability, light weight, high strength, high efficiency, flame retardance, fire resistance, controllable quality, water resistance, alkali resistance, freezing and thawing resistance, cracking resistance, falling resistance and the like.

A method of delivering an admixture providing freeze-thaw resistance to a cementitious composition is provided which includes the addition of a viscosity modifying admixture containing at least one of polymeric microspheres, at least partially degradable polymeric particles, or gas generating additives to cementitious compositions. The polymeric microspheres, at least partially degradable polymeric particles, and gas generating additives provide void spaces in the material matrix, and such void spaces act to increase freeze-thaw durability of the material.

The invention relates to a testing apparatus used for measuring the repeated expansion and shrinkage of a soil sample and a use method thereof. The device comprises a heating water tank 1, a loading frame 8, an evaporator 14, a freeze and thaw collapse chamber 17, a sample box 19, a weight 24, a pressurization lever 28 and the like. The testing apparatus has simple manufacture, high measurement precision and accurate temperature control, satisfies the requirements of freeze and thaw collapse of the soil sample and can be used for measuring the expansion and shrinkage amount and the volume change of various frozen and thaw collapsed soil textures in civil engineering. The testing apparatus is not only suitable for measuring under a pressure free expansion and shrinkage environment without load but also is suitable for measuring under a confining pressure environment with vertical load.

The invention relates to a talus slope freezing and thawing circulating action deformation physical model experiment apparatus and experimental method. The talus slope freezing and thawing circulating action deformation physical modeling experiment apparatus comprises a base placed on a talus slope, wherein a metal base plate and an organic glass model box are sequentially arranged on the base from bottom to top; a front door is arranged on the organic glass model box; a water drainage hole is formed in the bottom of the front door; a flow velocity rheometer is arranged between the water drainage hole and the front door; snow melting devices are respectively arranged on the two sides, and at the front part and the top of the organic glass model box; a thermometer is arranged at the top of the organic glass model box; a loading device is arranged at the rear part of the organic glass model box; at least a displacement meter is arranged inside the talus slope. The experiment apparatus disclosed by the invention can solve the problems that the existing talus slope physical simulator is single in test result, unstable in test result and incapable of simulating the freezing and thawing circulating action, has the characteristics of being convenient to operate and high in testing efficiency, and is suitable for simulation tests on slope deformation and breakage induced by freezing and thawing circulation and tunnel portal slope excavation.

The invention belongs to the technical field of application of cellulose and relates to a nano cellulose hydrogel and aerogel and a preparation method and application thereof. The preparation method of the nano cellulose hydrogel comprises the following steps: (a) pre-treating the cellulose raw material to obtain nano cellulose dispersion liquid; (b) mixing the nano cellulose dispersion liquid with a cross-linking agent to obtain compound dispersion liquid; and (c) freezing and thawing the compound dispersion liquid to obtain the nano cellulose hydrogel. The invention innovatively adopts the freezing and thawing treatment to successfully realize chemical cross-linking of nano cellulose; the product has the characteristics of low grade, high strength, high elasticity, high porosity and thelike and also has the advantages of mild conditions, strong operability and the like; and a feasible method is provided for preparation of nano cellulose gels and has industrialized application prospects.

The present invention relates to antifreezing concrete, which is prepared by the following components by weight percent: 16.5-17.0% of Portland cement or ordinary Portland cement, 6-7% of water, 26.5-27.5% of fine aggregate, 34.5-37% of coarse aggregate, 12.5-15.0% of a phase change material, and 1.0-2.0% of an additive, wherein the phase-transition temperature of the phase change material is 4.0-6.0 DEG C, and the enthalpy of phase change is 240-270 J/g. The beneficial effects of the invention are that: the antifreezing concrete containing the phase change material provided by the present invention effectively uses the specific thermal performance of the phase change material in order to prevent the occurrence of freezing and thawing cycles or reduce times of suffering freezing and thawing cycles. Therefore, when the temperature is not too low, especially in late autumn, early winter, late winter and early spring, the influence on traffic safety of concrete bridge and road surface from freezing can be effectively prevented. In severe cold areas, the damage or deterioration degree of concrete structures caused by repeated freezing and thawing can be relieved. For concrete projects constructed in winter, concrete before reaching critical strength can be prevented from freezing damage.

The invention aims to provide a preparation method of a magnesium oxysulfate binding material artware and the magnesium oxysulfate binding material aiming to solve the problem in the prior art that amagnesium oxysulfate binding material suitable for preparation of artware does not exist and based on the waste reutilization aim, belonging to the technical field of magnesium artware materials. Thepreparation method comprises the following steps: 1) brushing a release agent on the inner surface of a mold by a cleaning mold; 2) preparing the magnesium oxysulfate binding material; and 3) making the artware in the mold by adopting a pasting method. The artware made by the method does not need to be maintained, has the apparent density of more than or equal to 0.80 g/cm<3>, the water absorptionrate of less than or equal to 20.0%, the moisture content of less than or equal to 12.0%, the chloride ion dissolution quantity of less than or equal to 3.0%, the rupture strength of more than or equal to 6.5MPa, the compressive strength of more than or equal to 30.0MPa and the softening coefficient of more than or equal to 0.8, and is not damaged or cracked after 25 freezing and thawing cycles.Moreover, low-grade magnesite and other industrial and agricultural wastes are fully utilized, and the cost of the product is reduced.

A freeze and thaw system using knowledge-based hardware and methodology is provided for repair of oil-filled pipes. Liquid nitrogen is boiled off inside freeze jackets installed over the pipe, exiting in a superheated vapor state. Liquid nitrogen flow rates, controlled by the temperature controllers, are based on the requirements of the freeze process to maintain a desired level of superheat. The freeze operation is divided into distinct phases each with a different nitrogen superheated exhaust temperature. At the end of the repair, electric heaters wrapped over the pipe proceed to thaw the frozen oil. The heater controller thaws the frozen plugs based on an embedded time versus temperature protocol. The freeze prevention heaters are wrapped over the freeze jackets to prevent ice formation over the cold freeze jackets while the freeze plug is formed and maintained. This technology results in less thaw and freeze time at reduced liquid nitrogen usage.

The present invention relates to methods and structures for preparing stem cells for use in cryopreservation methods. Stem cell colonies are provided between first and second matrix portions and are exposed to a carbohydrate-containing cryoprotecting medium and a freezing medium. The methods of the invention yield cryopreserved cells that maintain cell viability and exhibit limited cell differentiation after freezing and thawing, facilitating storage, shipping and handling of embryonic stem cell stocks and lines for research and therapeutics.

The invention relates to an extract method of cordyceps militaris adenosine and belongs to the technical field of biological product processing. The extract method provided by the invention mainly comprises the following steps: superfine pulverizing cordyceps militaris fruiting body under low temperature, then repeating freezing and thawing for 3 to 7 times in order to destroy the internal components of the cellular interior, and further damaging the cell wall of cordyceps militaris, simulating the human gastrointestinal tract acid-base environment, extracting adenosine in cordyceps militaris by microwave heating using bio-mimetic extract technology for three times, finally measuring the content of adenosine in the extract using high performance liquid chromatography. In the invention, human gastrointestinal tract acid-base environment is simulated to extract cordyceps militaris adenosine, acid-base environment is not only favor of forming a salt from adenosine and dissolving, but also the obtained adenosine has a high extraction rate, which is easy to proceed subsequent separation and purification process, also easy to be proceeded into various types of medicament. The invention ensures the active ingredient of cordyceps militaris is absorbed directly, and the gastrointestinal burden is reduced.

The invention discloses a method for preparing phycocyanin by using bloom cyanophyte. Said invention uses the fresh bloom cyanophyte as raw material, and adopts the following steps: first step, extracting crude filtrate; dehydrating fresh bloom cyanophyte, adding buffer solutio, mixing them uniformly, frezing, takingout and thawing at room temperature, freezing and thawing for 3-5 times and filtering by using plate and frame; second step, ultrafiltering and purification; using hollow fibre ultrafiltration device whose trapping molecular weight is 1000-200000 daltons to remove various substances with smaller molecular weight from crude extract passed through microfiltration by using ultrafiltering membrane; third step, settling-clearing purification; removing most of small molecules from phycocyanin portion purified by means of ultrafiltration, at the same time making concentration and storing the concentrated phycocyanin portion at a certain temperature; and fourth step; hydroxyapatite column chromatography to make purification.

The invention discloses a preparation method of the acellular dried active amnion, comprising the following steps: (1) material processing: taking a human placenta which passes the detection of pathogen and obtained from a full term cesarean section, washing the human placenta with aseptic normal saline, removing blood components from the human placenta, blunt dissecting the amnion from the human placenta perfectly, striking off matrix components from the amnion substrate with a cell curet; (2) repeatly freezing and thawing; (3) washing; (4) freeze drying; and (5) disinfecting and sterilizing with gamma-ray. The method adopts the combination of repeat freeze-thaw method and using decontaminating agent to remove amnion cells, overcomes the defects of bad effects of removing cells by using freeze-thaw method alone, removes amnion cells effectively, keeps the integrity of collagen structure and basement membrane in tissue well, and keeps good mechanical property and no cytotoxicity.

A filter unit for liquids undergoing freezing for a metering unit of an exhaust gas treatment unit has a housing having an outer member and a lid member. At least one filter insert is arranged in the housing. An elastically deformable casing part is provided that surrounds at least partially the filter insert. The elastically deformable casing part is a part of the lid member or of the outer member of the housing and is made of a thermoplastic synthetic material. When the liquid undergoes freezing and thawing in the filter unit, the elastically deformable casing part can compensate the volume changes caused by freezing and thawing.