Methods of obtaining nanocrystalline cellulose from bagasse

FIELD: chemistry.

SUBSTANCE: method includes crushing and fractioning of initial material, delignification of initial raw material by alkaline hydration and alkaline pulping with further washings. After that, two-stage acidic hydrolysis with intermediate neutralisation and three washings is performed. Then, three-stage bleaching with hydrogen peroxide H2O2 with three washings is carried out. In second washing finely dispersed ozone is supplied. Obtained product is additionally subjected to homogenisation and drying. Invention makes it possible to obtain final product with virtually absolute absence of lignin, with high organoleptic and physical and chemical properties from lignin-containing initial material.

EFFECT: method does not require application of expensive equipment, does not involve application of highly toxic reagents, includes simple technological operations, is characterised by production scalability.

3 cl, 3 dwg, 1 ex

 

The invention relates to a method of producing nanocrystalline cellulose fibres from plant material of different origin. The resulting material has a wide application in non-food industries, in particular, in the production of high quality papers in the medical industry as adsorbents, in the cosmetic industry as a natural thickener, as well as in the food industry as a natural krahmalosoderzhaschih thickener.

A method of producing cellulose from straw, comprising impregnation in the reactor and maceration straw chaff with an aqueous solution of sodium hydroxide at a temperature of 30-80°C when the mass ratio of solution to mass of dry chaff 7:1; impregnated particles maintained at a predetermined temperature for 30 minutes collect dripping liquid phase, added to the mass of heated water, raise the temperature to 96°C, carry out the cooking at this temperature for 2 hours 30 minutes (patent RU 2423570, publ. 10.07.2011). This method increases the yield of pulp, reduces the duration of the process, it provides simplification and reduction of energy costs, however, does not allow to obtain a finished product with the claimed properties.

A method of producing pulp from flax raw materials, including loosening and cleaning flax-zelenec or flax straw, rinsing and cutting mater�Ala, his soaking, termomekhanicheskoe processing, rinsing and bleaching, rinsing, wringing and drying. After termomekhanicheskoi processing cellulosic material ripening is carried out in an alkaline solution (patent RU 2343241, publ. 10.01.2009). This method allows to increase the efficiency of the method of obtaining cellulose, however, does not allow to obtain a product with the claimed properties.

A method of producing cellulose from wheat straw, which is subjected to partial hydrolysis in a solution containing acetic acid, hydrogen peroxide and sulfuric acid, at a temperature of 100°C, the water ratio 1:10 for 2 hours. The mass was then suspended in pyridine for 12 hours. The sulfation is carried out at a temperature of 80-85°C for 1.5-2 hours. The product is separated, washed with ice-cold water, transferred into a sodium salt. Decanted aqueous solution, the desired product was washed with ethanol, filtered and dried (patent RU 2426746, publ. 20.08.2011). The method allows to simplify the method of producing a sulfated cellulose by reducing the duration of sulfation, however, involves the use of highly toxic reagents.

A method of producing cellulose from straw of rice, including two stage pulping of rice straw. The first stage of melting lead in an alkaline medium, followed by separation of cellulosic products�and, the second stage of cooking are in an acidic environment with a mixture of peracetic acid, acetic acid and hydrogen peroxide in the presence of the stabilizer, which is used as a mixture organophosphonates. The second stage of cooking carried out in the presence of ozone (patent RU 2418122, publ. 10.05.2011). This method reduces the amount of composition on the basis of peracetic acid, to increase the yield of the target product, reducing the content of lignin and increase the performance of whiteness, however, does not allow to obtain a product with the claimed properties.

Closest to the invention to the technical essence is a method of producing microcrystalline cellulose from cereal straw, which is carried out by combining the processes of delignification and hydrolysis of milled wheat straw, with the original processing of the raw material solution containing a mixture of acetic acid and hydrogen peroxide in the presence of sulfuric acid catalyst, at a temperature of 110-140°C for 2-4 hours, then the resulting fibrous product is treated with a mixture of acetic acid and hydrogen peroxide at a temperature of 100-120°C for 1-3 hours (patent RU 2312110, publ. 10.12.2007). This method is economical due to the reduction of liquor ratio and regeneration of solutions of acetic acid, however, does not allow to obtain a product with the claimed properties.

Wiseprice�Lenno disadvantages of the known methods, each separately or all together, reduce the degree of functionality of the finished product, require the use of toxic reagents, increase the cost of production, does not allow to obtain a product with the claimed properties.

The object of the invention is to develop an economical method of producing nanocrystalline cellulose from lignin-containing raw materials, in particular from dry milled bagasse, with almost complete absence of lignin in the finished product without the use of harsh and toxic chemicals.

The method is characterized by the following set of essential features:

1) perform a simple technological operations;

2) avoid the use of sulfur compounds as a catalyst in mercerizing;

3) the use of low-toxic reagents in a minimum volume;

4) the use of the closed cycle of water supply and reuse alkaline solutions;

5) environmental safety;

6) reducing energy costs;

7) scalability of production.

The technical result of the invention is to improve the quality of the finished product with a set of significant characteristics:

1) is a regulator of the rheology in the production of products with the desired viscosity and texture through the formation with�precise structures through intermolecular bonds;

2) consists of a highly ordered crystalline areas;

3) has high absorbent and adsorbent properties;

4) has a high rate of water retention;

5) practically no lignin in the final product. The technical result is achieved in that the dry bagasse moisture content of 7-9%, with the content of lignin 18-24%, ground and fractionary to particle size of 1-2 mm, is subjected to alkaline hydration in 1% NaOH solution, additionally serves NaOH to a concentration of 4-8%, adjusted to a temperature of 170-180°C for 1.5-2.5 hours, wring out in a centrifuge or other Timna equipment, washed in tap water, distilled or softened water, wring out, washed in 0.5% acetic acid at a temperature of 40-45°C for 5-15 minutes with constant stirring, squeeze, spend the first stage of acid hydrolysis in a solution of oxalic acid at a temperature of 75-80°C for 1.5-2 hours, neutralization is carried out by adding 25% ammonia solution NH4OH, with constant stirring, to pH=3, carry out the second stage of acid hydrolysis by adding 35% HCl solution, without unloading and spinning, to pH=1,4-1,5, at a temperature of 70-75°C for 1-2 hours, with constant stirring, squeeze in a centrifuge or other Timna equipment, spend three washing in distillers�by the auditors or softened water temperature 30-60°C, with constant stirring, for 10 to 20 minutes, spin in a centrifuge or other Timna equipment after each washing, bleaching is carried out by adding to distilled water at a temperature of 40-45°C 25% aqueous ammonia solution NH4OH to working pH of 10.3 to 11, making pressed pulp, phased introduction of a 33% solution of hydrogen peroxide (H2O2slow controlled heating to a temperature of 80-95°C, add 25% solution of NH4OH when the temperature reaches 60-65°C, a total bleaching of 1.5-2.5 hours after reaching a temperature of 65°C, press on the centrifuge or other Timna equipment, conduct first rinsed in softened or distilled water of temperature of 60-80°C, for 5-10 minutes, press on the centrifuge or other Timna equipment, conduct a second wash in distilled water at a temperature of 50-55°C, with flow melkodispersnogo of ozone in the stream of purified air through 4-6 minutes after the start of flushing, General washing 20-25 minutes, press on the centrifuge or other Timna equipment spend a third rinsing in distilled water at a temperature of 30-60°C for 5-20 minutes, with constant stirring, squeeze in a centrifuge or other Timna equipment.

The technical result is achieved by:

1) select optimal�'s temperature and time indicators of process steps;

2) the optimal combination of organic and inorganic acids during acid hydrolysis, providing safety fibers and a high degree of rheology of the product;

3) selection of optimum process water quality;

4) using the neutralization of the alkali.

The method is implemented as follows.

In the production of nanocrystalline cellulose fibers as raw material use annual plants, in particular bagasse.

Dry bagasse moisture content of 7-9%, with the content of lignin 18-24% crushed and fractionary to particle size of 1-2 mm.

The obtained fraction was placed in a 1% solution of NaOH at a temperature of 45-50°C, the optimum water ratio 1:20, and incubated for 30 minutes with constant stirring at a stirrer rpm 30-40 rpm.

Further, in the reactor additionally served NaOH to a concentration of 4-8%, preferably 6-8%, optimally 6%, with a gradual controlled rise in temperature to 170-180°C, optimally 175°C, for 1.5-2.5 hours, optimally 2 hours, with constant stirring at a stirrer rpm 30-40 rpm as a result of the operations of the lignin content is reduced to 6-8 times (the lignin content after mercerization is less than 3% compared with the initial content of lignin 18-24%).

The pulp is then squeezed in a centrifuge or other�Ohm Timna equipment with a speed of 1000-1500 rpm, preferably 1000-1200 rpm, optimally 1200 rpm for 15-30 minutes, preferably 15-20 minutes, ideally 20 minutes.

Next spend washing in tap water, distilled or softened water, preferably distilled or softened, optimally softened in water, when the water ratio 1:30, the temperature of 80-85°C for 15 minutes with constant stirring at a stirrer rpm 30-40 rpm.

After time, the pulp is squeezed in a centrifuge or other Timna equipment under similar conditions of extraction.

The resulting pulp was washed in 0.5% acetic acid at a temperature of 40-45°C for 5-15 minutes with constant stirring to block the action of alkali.

Then subjected to spinning in a centrifuge or other Timna equipment under similar conditions of extraction.

Get raw neutralized mercerized pulp humidity up to 93%.

The resulting crude neutralized mercerized pulp is mixed with distilled water at a temperature of 45°C, add the dry crystalline oxalic acid to pH=0,5-0,8, optimum pH=0,7, acid hydrolysis is carried out in oxalic acid at a temperature of 75-80°C, optimally at 75°C for 1.5-2 hours, with constant stirring.

To the resulting solution was added 25% ammonia solution NH4OH Pocatello, just�nom stirring, to pH=3.

Then, without unloading and pressed, adding 35% HCl solution to pH=1,4-1,5, hydrolysis is carried out at a temperature of 70-75°C for 1-2 hours, preferably 1-1,5 hours, optimally 1 hour, under constant stirring.

After a time they spin in a centrifuge or other Timna equipment under similar conditions of extraction.

Next spend three flushing.

The first washing is carried out in distilled water at a temperature of 30-60°C, preferably 40-50°C, optimally 45°C, with constant stirring, for 10 to 20 minutes, preferably 15 minutes.

Then spin in a centrifuge or other Timna equipment.

The second and third operations of the washing-spinning is carried out as the first.

Then subjected to bleaching.

When bleaching as a bleaching reagent is a peroxide, as the alkaline agent is aqueous ammonia.

In distilled water at a temperature of 40-45°C, optimally 45°C, add 25% aqueous ammonia NH4OH to working pH of 10.3 to 11, preferably of 10.7 to 10.9, make the pulp and at a temperature of 40-45°C, optimally 45°C, making the first portion of a 33% solution of hydrogen peroxide (H2O2in the amount of 2/3 of the required amount. Next produce a slow controlled heating to a temperature of 50-55°C, optimally at 55°C, and provide the second portion of H2O2in the amount of 1/6, uncut�entered as much as possible volume. When the temperature reaches 60-65°C, optimum 65°C, make a third portion of a 33% solution of H2O2in the amount of 1/6 of the required amount and 25% of R-R NH4OH to a pH of 10.7-10.9, continue slow controlled heated to 80-95°C. the Total time of bleaching is 1.5-2.5 hours, optimally 2 hours after reaching a temperature of 65°C.

After this time the pulp is squeezed in a centrifuge or other Timna equipment under similar conditions of extraction.

Next spend three flushing.

The first washing is carried out in a softened or distilled water at a temperature of 60-80°C, preferably 60-75°C, optimally at 75°C, for 5-10 minutes, optimally 5 minutes of receipt of the first portion of the pulp.

After this time they spin in a centrifuge or other Timna equipment.

A second rinse is carried out in distilled water at a temperature of 50-55°C, with flow melkodispersnogo of ozone in the stream of purified air through 4-6 minutes after the start of washing, optimally in 5 minutes, for 20-25 minutes, at a speed of 200 l/hour.

Then spin in a centrifuge or other Timna equipment under similar conditions of extraction.

Next produce a third rinsing in distilled water at a temperature of 30-60°C, preferably 40-50°C, optimally 40-45°C for 5-20 minutes, preferred�tive 10-15 minutes optimal 15 minutes of receipt of the first portion of the pulp, with constant stirring.

Then spin in a centrifuge or other Timna equipment under similar conditions of extraction.

The result is a nanocrystalline cellulose product is white, without any shades with uniform plastic consistency, odorless, with anonymised taste, without impurities and inclusions, without separation of the aqueous phase, humidity up to 93%, with a mass fraction ACC 8%, mass fraction of cellulose is 7.8%, with the absence of lignin.

The resulting product can be used in the production of high-quality paper, as a sorbent in the medical industry in the manufacture of wound dressings, absorbent bed sheets, diapers, and highly selective rapid test systems for production of serums, vaccines, immunomodulators, antihistamines; in the cosmetic industry as a natural thickener.

The resulting product may be subjected to additional stages of homogenization for the purpose of obtaining hydrogel. To do this, the resulting product was diluted with distilled or softened water hardness not more than 0.2°W to the desired solids content, stirred until a homogeneous mass, twice passed through the homogenizer PR� pressure 150-350 atmospheres at a temperature of 18-25°C, optimum 20°C. the result is 1.5% of the hydrogel nanocrystalline cellulose, transparent, colorless, smooth, without separation into phases within 72 hours and more, without foreign smells, with anonymised taste, with a pH of 6.8 to 7.2, a viscosity of 4000-4500 SP.

By drying the obtained hydrogel on glass at 20-25°C for 2-2,5 hours to form a film thickness of 1 mm, characterized by a homogeneous structure without dense inclusions, absolute transparency, colourless and moderate fragility.

Brief description of the drawings

Fig. 1. Nanocrystalline cellulose product, W=92,6.

Fig. 2. Hydrogel nanocrystalline cellulose (NCC) 1.5% ACC.

Fig. 3. The dried hydrogel NCC in the form of a film.

The invention is further described in the following not limiting the scope of the present invention examples.

Example 1

Dry bagasse in an amount of 200 g, moisture 7%, lignin content of 24%, was subjected to grinding and fractionation to particle size of 1-2 mm.

The obtained fraction was subjected to alkaline hydration in 1% NaOH solution at a temperature of 45°C, the water ratio 1:20, for 30 minutes with constant stirring at a stirrer rpm 30-40 rpm.

Further implemented the mercerization in 6% NaOH solution, at a temperature of 175°C, for 2 hours, with constant stirring with� the stirrer rpm 30 rpm.

Once the time has produced a spin in a centrifuge at a speed of 1200 rpm for 20 minutes.

Pressed pulp is washed in distilled water at a water ratio of 1:30, a temperature of 80°C for 15 minutes with constant stirring at a stirrer rpm 30 rpm and pressed under similar conditions of extraction.

Pressed pulp is washed in a 0.5% solution of acetic acid at a temperature of 45°C, the water ratio 1:30, for 10 minutes with constant stirring.

After time, the pulp is pressed in a centrifuge at a speed of 1200 rpm for 20 minutes. The output of 1 kg of raw mercerized pulp humidity 92,6%, lignin content of 2.5%.

The resulting pulp was mixed with distilled water at a temperature of 45°C, in the amount of 4000 ml), washed for 15 minutes with constant stirring, added the dry crystalline oxalic acid in an amount of 215 g, spent acid hydrolysis in oxalic acid at a temperature of 75°C for 2 hours, with constant stirring, to pH=0,7.

To the resulting solution was added 140 ml of 25% ammonia solution NH4OH Pocatello, with constant stirring, to pH=2,9.

Then, without unloading and spinning, added 35% aqueous HCl (100 ml to pH=1,4, spent the hydrolysis at a temperature of 75°C for 1 hour with constant stirring.

After the time �the Hulpe pressed in a centrifuge under similar conditions of extraction.

Pressed pulp is mixed with distilled water with a volume of 3000 ml, temperature 45°C, produced the first washing with constant stirring, for 15 minutes.

After time, the pulp is pressed in a centrifuge under similar conditions of extraction.

Pressed pulp is mixed with distilled water with a volume of 3000 ml, temperature 45°C, produced a second flush with constant stirring, for 15 minutes.

After time, the pulp is pressed in a centrifuge under similar conditions of extraction.

Pressed pulp is mixed with distilled water with a volume of 3000 ml, temperature 45°C, produced the third rinsing with constant stirring, for 15 minutes.

After time, the pulp is pressed in a centrifuge under similar conditions of extraction. The output of 280 g of the pulp moisture content of 70.8%.

In distilled water with a volume of 2000 ml, a temperature of 45°C was added 12.5 ml of 25% aqueous ammonia NH4OH to working pH of 10.7, made 280 g of pressed pulp, introduced 400 ml of 33% solution of hydrogen peroxide H2O2fired slow controlled temperatures up to 55°C, introduced 100 ml of a 33% solution of hydrogen peroxide H2O2fired slow controlled heating to 65°C, introduced 100 ml of a 33% solution of H2O2and 25% p-p NH4OH to pH=10,9, continued slow controlled heating to 85°C. General�the time bleaching was 2 hours after reaching a temperature of 65°C. After this time the pulp is pressed in the centrifuge.

Pressed pulp is mixed with 1500 ml of distilled water at a temperature of 75°C, carried out the first rinsing within 5 minutes of receipt of the first portion of the pulp. After a specified time has produced a spin in a centrifuge under similar conditions of extraction.

Pressed pulp is mixed with distilled water in the amount of 1500 ml, a temperature of 55°C and began washing, after 5 minutes of rinsing filed melkodispersionnyy ozone in a stream of purified air and continued supply of ozone for 20 minutes, without stopping the process of washing. Once the time has produced a spin in a centrifuge under similar conditions of extraction.

Pressed pulp is mixed with distilled water with a volume of 1500 ml and a temperature of 45°C, produced the third rinse for 10 minutes with constant stirring. Then made a spin in a centrifuge under similar conditions of extraction.

The output of nanocrystalline cellulose product in the amount of 272 g, white, without any shades, without impurities and inclusions, with a uniform plastic consistency, odorless, with anonymised taste, without separation of the aqueous phase, humidity 92,6%, with a mass fraction ACC 8%, mass fraction of cellulose is 7.8%, with the absence of lignin.

The product obtained in kolichestvo g was diluted with distilled water 1000 ml, stirred until a homogeneous mass, missed twice through a homogenizer at a pressure of 250 atmospheres at a temperature of 20°C. At the outlet received 1.5% of the hydrogel nanocrystalline cellulose in the amount of 1300 g, clear, colorless, smooth, without separation into phases, odor-free, with anonymised taste, pH=7.0, a viscosity of 4000 SP.

The obtained hydrogel was dried on the glass at 20-25°C for 2 hours. Got a film thickness of 1 mm, with homogeneous structure, without dense inclusions, totally transparent, colorless, with moderate fragility.

1. A method of producing nanocrystalline cellulose, comprising grinding the dry bagasse moisture content of 7-9%, with the content of lignin 18-24%, fractionation prior to particle size of 1-2 mm, alkaline hydration in 1% NaOH at a temperature of 45-50°C, the water ratio 1:20, for 30 minutes with constant stirring at a stirrer rpm 30-40 rpm, the addition of NaOH to a concentration of 4-8% at a gradual controlled heated to 170-180°C for 1.5-2.5 hours, with constant stirring at a stirrer rpm 30-40 rpm, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, rinse in tap water, distilled or softened water at a water ratio of 1:30, the temperature of 80-85°C for a period�their 15 minutes with constant stirring at a stirrer rpm 30-40 rpm, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, rinsed in 0.5% acetic acid for 5-15 minutes, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, the first stage of acid hydrolysis in a solution of oxalic acid at a temperature of 75-80°C for 1.5-2 hours, with constant stirring, neutralized by adding 25% ammonia solution NH4OH, Pocatello, with constant stirring, to pH 3, the second stage of acid hydrolysis by adding 35% HCl solution, without unloading and spinning, to a pH of 1.4 to 1.5, at a temperature of 70-75°C for 1-2 hours, with constant stirring, spinning in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, the first rinsing in distilled water at a temperature of 30-60°C, with constant stirring, for 10-20 minutes, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, second wash in distilled water at a temperature of 30-60°C, with constant stirring, for 10-20 minutes, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, the third rinsing in distilled water at a temperature of 30-60°C, prepostional stirring, within 10-20 minutes, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, bleaching by adding to distilled water at a temperature of 40-45°With 25% aqueous ammonia solution NH4OH to working pH of 10.3 to 11, making pressed pulp, add the first portion of the 33% solution of hydrogen peroxide H2O2in the amount of 2/3 of the required volume at a temperature of 40-45°C, slow controlled heating to a temperature of 50-55°C, add the second portion of a 33% solution of N2O2in the amount of 1/6 of the required amount, slow controlled heating to a temperature of 60-65°C, add a third of a 33% solution of N2O2in the amount of 1/6 of the required amount and a 25% solution of NH4OH to a pH of 10.7 to 10.9, slow controlled heating to a temperature of 80-95°C, with a total time of bleaching of 1.5-2.5 hours after reaching a temperature of 65°C, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, first rinse softened or distilled water of temperature of 60-80°C, for 5-10 minutes, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, second wash in distilled water at a temperature of 50-55°C, filing melodicity�created ozone in a stream of purified air through 4-6 minutes after the start of washing, at a speed of 200 l/hour, with the total flushing time of 20-25 minutes, spin in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes, the third rinsing in distilled water at a temperature of 30-60°C for 5-20 minutes, with constant stirring, spinning in a centrifuge or other Timna equipment with a speed of 1000-1500 rpm for 15-30 minutes.

2. A method according to claim 1, characterized in that the product obtained is diluted with distilled or softened water hardness not more than 0.2°W to the desired solids content, stirred until a homogeneous mass, twice passed through the homogenizer at a pressure of 150-350 atmospheres at a temperature of 18-25°C.

3. A method according to claim 2, characterized in that the finished homogenized product was dried on the glass at 20-25°C for 2-2,5 hours.



 

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1 tbl

FIELD: medicine.

SUBSTANCE: invention describes a method for producing Sel-Plex nanocapsules possessing the supramolecular properties by non-solvent addition, characterised by the fact that Sel-Plex is dissolved in dimethyl sulphoxide; the prepared mixture is dispersed in xanthum gum solution used as a nanocapsule shell, in butanol, in the presence of E472c preparation while stirring at 1000 cycles per second; the mixture is added with the precipitator benzol, filtered and dried at room temperature.

EFFECT: simplifying and accelerating the process of nanoencapsulation and ensuring higher weight yield.

4 ex, 12 dwg

FIELD: chemistry.

SUBSTANCE: ceramic membrane, applied for the separation of gas mixtures, has the following composition, wt %: aluminium oxide 30-54; sodium silicate 42-68; carbon nanotubes CNT with an external diameter of 1-5 nm with a three-layer structure and a specific surface of 350-1000 m2/g 1-4. The method of preparing the ceramic membrane for the separation of gas mixtures includes mixing of thermoactivated gibbsite - Al(OH)3 with sodium silicate and the carbon nanotubes CNT with an external diameter of 1-5 nm with the three-layer structure and the specific surface of 350-1000 m2/g, following addition of a nitric acid solution. The obtained mass is thoroughly mixed and an excess of moisture is removed until powder has a half-dry condition. The obtained powder is pressed, the pressed tablets are subjected to thermal-processing - first, they are exposed at a temperature of not higher than 150°C, then at a temperature of not higher than 400°C. The obtained membrane in the form of a tablet is annealed without air access at 850-1100°C.

EFFECT: increased factor of the gas mixture separation.

2 cl, 3 dwg, 2 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention relates to electronics and is intended to design devices which convert the chemical reaction of adsorbed molecules of a fuel gas (vapour) and oxygen (or air) into an electrical signal. The invention can be used to design compact batteries for electronic equipment in the form of single-chamber fuel cells, which consist of a working chamber having a fuel-gas mixture inlet and a gas outlet, inside of which there is a composite film with electrical contacts connected to an external load, the space between which is filled with a conducting material. The conducting material used is a nanocomposite material which consists of a non-conducting polymer film of polypropylene and conducting filler in the form of carbon nanotubes. Concentration of the carbon nanotubes with p-type conductivity is about 0.5-5% near the percolation threshold. The nanocomposite material may contain catalytic nanoparticles of Pt or Pd, or Rh, or Ru. Also disclosed is a method of producing a conducting nanocomposite material, which includes mixing carbon nanotubes and polymer material and then holding the nanocomposite material at external voltage of 4-10 V for 2-30 min in an atmosphere of saturated acetone vapour.

EFFECT: higher current density in the active layer.

7 cl, 3 dwg

FIELD: medicine.

SUBSTANCE: invention refers to medicine and describes a method for producing chondroitin sulphate nanocapsules by non-solvent addition, characterised by the fact that chondroitin sulphate is added in small portions into xanthane gum suspension used as a nanosuspension shell, in butanol containing 0.01 g of the preparation E472 as a surfactant; the produced mixture is stirred and added with the nonsolvent hexane 6ml, filtered, washed in hexane and dried.

EFFECT: invention provides simplifying and accelerating the process of nanoencapsulation in xanthane gum and higher weight yield.

2 ex

FIELD: medicine.

SUBSTANCE: invention represents a method for drug encapsulation by non-solvent addition, wherein according to the invention cores of nanocapsules are vitamins, whereas a shell is sodium carboxymethyl cellulose precipitated from isopropyl alcohol suspension by adding chloroform as a non-solvent and dried at room temperature.

EFFECT: simplifying and accelerating the process of nanoencapsulation, reducing accompanying loss.

7 ex

FIELD: medicine.

SUBSTANCE: invention relates to field of biotechnology. Method of extracting DNA from blood cells is claimed. Magnetic particles and ferromagnetic nanospheres CoNiFe2O4 50 nm are added into sample. Biologic material is lysed. DNA is washed and DNA is taken off from carrier.

EFFECT: preference of claimed method consists in increase of DNA quantity in obtained sample.

3 dwg, 1 ex

FIELD: heating.

SUBSTANCE: invention relates to formation methods of independent self-cooled instruments and elements of electronics, which can operate effectively without using any liquid nitrogen technology and other cryogenic equipment. The formation method of an independent self-cooled nanoinstrument consists in the fact that on a substrate from monocrystalline material with a squid receiver formed on one side there arranged on the reverse side is a heat absorption device that includes a cathode and an anode, which have different Fermi energy of electrons. Then, the substrate is enclosed through an installation hole in a vacuum cover from ceramised glass which contains contact electrodes for two substrate sides. After that, the substrate installation hole is closed with a cover from ceramised glass. This device is arranged in a vacuum chamber in which a target from ceramised glass is arranged as well. Pumping-out to the pressure of 10-1 Pa is performed; the target and the cover from ceramised glass is heated up to 450÷500°C. Then, by means of a laser with wavelength of radiation equal to 1.06 mcm, pulse duration of 10-20 ns and pulse repetition frequency of 10 Hz, power density of 5·108÷8·108 W/cm2 there the target from ceramised glass is sprayed, which is located at the distance of 8÷10 mm from the cover from ceramised glass during 10 minutes.

EFFECT: invention provides creation of such design of a squid (a superconducting quantum interference device), in which the following is excluded: degradation of superconducting properties in the air medium, dependence of achievement of operating temperature on use of liquid nitrogen or other external cryogenic units with large dimensions.

1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to pigments for white paints and coatings, including temperature-control coatings of spacecraft, and can be used in space engineering, in the construction industry and in various industries for temperature control of devices or processing facilities. The pigment for light-reflecting coatings is obtained by heating at 800°C and with a high vaporised and ground mixture of titanium dioxide microparticles with 7 wt % silicon dioxide nanoparticles.

EFFECT: invention enables to obtain a pigment with high radiation resistance using a simple technique which is efficient compared to similar pigments obtained using prior art.

1 tbl, 8 ex

FIELD: medicine.

SUBSTANCE: described is a method of obtaining a composite chitosan-based material, which contains aspartic or glutamine amino acids in a quantity from 2 to 5 wt %, as well as calcium phosphates with a ratio of Ca/P from 1.0 to 1.67. The method consists in barbotage through a suspension of calcium phosphates, obtained in situ in a solution of chitosan and aspartic or glutamic acid, with the following lyophilic drying of the foamed products. Porous matrices can be applied in dentistry, maxillofacial surgery, osteoplastic surgery as implants in the treatment of bone tissue defects.

EFFECT: obtained samples are characterised by a uniform porous structure with the simultaneous reduction of calcium phosphate dimensions to a nano-level with the reduction of the number of material obtaining operations.

2 dwg, 5 ex

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to medicine, namely to a polymer composition for medical devices containing polycarbonate with a degree of polymerisation of n=200-2,000 in an amount of 100 weight fractions, a polymer additive, which is presented by polysulphon at a degree of polymerisation of n=70-150, in an amount of 5 to 40 weight fractions, a complex stabiliser, which is presented by sterically hindered phosphite in an amount of 0.045 to 1.5 weight fractions, a compatibiliser representing maleinised polypropylene in an amount of 0.025 to 5.0 weight fractions, a nanostructured additive representing carbon nanotube superconcentrate with the nanotube content of 20-40 weight fractions in butadiene oligomer with a degree of polymerisation of 6 in an amount of 0.01 to 1.0 weight fractions.

EFFECT: invention provides creating the polymer composition with high strength characteristics.

3 cl, 1 ex, 2 tbl

Food semi-product // 2535947

FIELD: food industry.

SUBSTANCE: invention relates to food industry. The food semi-product includes sodium carboxy-methylcellulose in an amount of 0.61-1.65%, ethyl alcohol in an amount of 50-74% and purified water till 100%. Water contains silver ions at a concentration of 0.3-4.5 g/l.

EFFECT: invention allows to increase the product storage life in case of the semi-product introduction into the product.

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