Method of obtaining magnetite nanoparticles, stabilised with polyvinyl alcohol
FIELD: chemistry.
SUBSTANCE: invention can be used in magnetic nanoelectronics for magnetic registering media with high recording density, for magnetic sensors, radio-absorbing screens, as well as in medicine. Method of obtaining magnetite nanoparticles, stabilised with polyvinyl alcohol, includes obtaining magnetite in alkali medium of mixture of salts of bi- and trivalent iron and polyvinyl alcohol with weight content in initial mixture from 4 to 18 wt %, dispersion, washing and carrying out all operations under continuous ultrasound impact. Process of sedimentation of salts of bi- and trivalent iron and polyvinyl alcohol is carried out in ammonia vapour, with application of aqueous ammonia (NH4OH) or hydrazine hydrate (N2H4·H2O).
EFFECT: invention makes it possible to reduce scatter of magnetite nanoparticles by size, reduce labour consumption and expenditures in the course of process.
2 dwg, 2 ex
The invention relates to the field of nano technology (specifically, to the field of polymeric nanocomposite based on the polyvinyl alcohol) and can be used in magnetic nano-electronics for magnetic recording media for high density recording, magnetic sensors, stealth screens and the like, as well as in medicine.
A known method of obtaining magnetite by coprecipitation of salts of divalent or trivalent iron excess alkali (see: Patent 4430239, ISM H01F 10/10. Ferrofluid Composition. Wyman J.E. USA).
During the realization of this patent, it is advisable to use a 10%salt solution (FeSO4·7H2O and FeCl3·6N2On) and pour in a solution of alkali or hold fast neutralization of the salt with an excess of alkali, as in the slow draining of dilute solutions are formed larger particles. To prevent the formation of iron hydroxide and other adverse processes using preferably chloride and ferric sulfate, and instead of caustic soda aqueous solution of ammonia. What if this chemical reaction can be expressed by the following equation:
The use of ammonia allows you to create soft conditions coprecipitation oxide, which contributes to reaction with the formation of it is finely dispersed magnetite composition of Fe2 O4or Fe2O3·FeO, which has the best magnetic characteristics in comparison with other magnetites, such as mFe2O3·nFeO (where n≠m), and the resulting ammonium salt NH4Cl when heated easily decomposes with evolution of ammonia gas. Ions Cl-and soluble salts are removed by repeated washing with distilled water. As a result, in the solution decreases the number of oppositely charged ions, causing coagulation of particles of magnetite or preventing their peptization in the carrier fluid (using the obtained magnetite in magnetic fluids).
However, the foregoing method and obtained by this method, the nanoparticles have a number of disadvantages:
a) no way to adjust the particle size of magnetite in the reaction, to limit their growth;
b) the method does not prevent aggregation of the obtained nanoparticles of magnetite;
C) obtained by the above method, the nanoparticles are chemically not protected, are highly reactive and quickly lose their properties when in contact with air.
Closest to the proposed method (prototype) is a Method of obtaining the magnetite nanoparticles stabilized biocompatible polymer having functional formyl group" (patent RF №2431472; and the Torah Yamskov IA, Tikhonov V.E., Loginova the like, includes I.A.). This method of obtaining nanoparticles of magnetite stabilized biocompatible polymer having available functional formyl group, includes obtaining magnetite from a mixture of salts of divalent or trivalent iron adsorbed in the polymer matrix, with subsequent modification of the end groups of the polymer. Magnetite receive joint deposition in an alkaline medium a mixture of salts of divalent or trivalent iron and at least one polymer selected from the range of: chitosan, polyvinyl alcohol, block copolymers of polystyrene and polyethylene oxide. The weight content of the polymer in the composite from 4 to 18 wt.%. The resulting composite is dispersed, treated with an aqueous solution of glutaraldehyde and washed. All operations are performed under continuous ultrasound exposure.
The invention allows to obtain stable nanoparticles of magnetite, are reusable.
The above method and obtained by this method, the nanoparticles have a number of disadvantages:
1). The high content of stabilizer on the surface and inside the nanoparticles significantly lowers operational magnetic properties of magnetite and seriously limits its application in magnetic nano-electronics.
2). The method is very time-consuming, in particular, C is the operation of processing the magnetite nanoparticles in an aqueous solution of glutaraldehyde. Note that this operation is not necessary for the magnetite nanoparticles used in electronics.
3). For the magnetite used in the magnetic electronics, sensors and the like, there is no need to use such expensive polymers like chitosan, block copolymers of polystyrene and polyethylene oxide.
4). Obtained by this method magnetite particles have a substantial range of sizes (according to our research - from 8 nm to 230 nm).
5). Upon receipt of the composite nanoparticles of magnetite in the form of a thin film or bulk material this way is not always possible to obtain a uniform structure of composite material, get rid of agglomerates of unreacted (reacted poorly) the source of the reaction products.
The purpose of the present invention consists of:
a) increase in functional magnetic properties of the magnetite nanoparticles for effective use in electronics devices, magnetic recording media, sensors, etc.;
b) reduction of the dispersion of nanoparticles of magnetite in size;
C) reducing the complexity and cost of the method (by eliminating some operations, reduce waste production by reducing the number of agglomerates, unreacted (reacted poorly) the source of the reaction products, and so what.);
g) obtaining a uniform structure of magnetite in the synthesis of composite nanoparticles of magnetite in the form of a thin film or bulk material.
The technical result is achieved by a method for production of nanoparticles of magnetite stabilized polyvinyl alcohol, including the production of magnetite in an alkaline medium a mixture of salts of divalent or trivalent iron and polyvinyl alcohol with a weight content in the initial mixture from 4 to 18 wt.%, dispersing, washing and conducting all operations under continuous ultrasound exposure, characterized by the fact that the process of deposition of a mixture of two - and trivalent iron and polyvinyl alcohol is carried out in pairs ammonia, using an aqueous solution of ammonia (NH4OH) or hydrazine-hydrate (N2H4·H2O).
The method is implemented as follows. In the first stage, prepare a solution of the polymer. Polyvinyl alcohol (PVA) dissolved in deionized water at a certain concentration (weight content in the initial mixture from 4 to 18 wt.% to obtain the maximum magnetization) to obtain a homogeneous solution, to accelerate the dissolution process vessel heated at 70°C, constantly stirring the solution. Later in the polymer solution make a joint solution of the compounds of ferric chloride III (6N2About·FeCl3) and chloride jelly is and II (4H 2O·FeCl2or sulphide of iron II (FeSO4·7H2O) in a ratio of two to one, in accordance with the standard method of obtaining chemical coprecipitation. The concentration of the metal calculated relative to the weight of the polymer. Thus, get the source precursors with different concentrations of metal.
As a restorative environment for synthesis is an aqueous solution of ammonia (NH4OH) with a concentration of 25% or hydrazine-hydrate (N2H4·H2O). The process of synthesis of the composite is carried out in a desiccator, the bottom of which is poured a solution of the carrier vapor of ammonia, and the top have a container with a solution of the precursor. After placing the samples for research in the desiccator, the required shutter speed, which depends on the number of the source precursor. The average dwell time is day. At the end of the synthesis is accomplished nanoparticles of Fe3O4in the PVA matrix.
When the hydrazine-hydrate (N2H4·H2O) allocates a pair of ammonia oxidation by the oxygen of the air in the desiccator, and oxidation can occur by the second type involving precursor.
Use this method as a restorative environment is vapor ammonia narrow distribution of particle sizes, due to uniform distribution of the reaction medium at su the mu volume of material, resulting in the closest samples to the regular structure. A pair of ammonia from the gas phase is easily dissolved in the aqueous environment of the precursor and uniformly impregnate the whole amount, without making changes to the initial ratio of the components, so there is no need for mixing. As a result, the entire volume of the precursor is the reaction, there is no concentration gradient (or the gradient - minimum) at all stations, which allows the particles to activate the process.
The next step after synthesis is washing the samples with deionized water to remove the reaction products. Particles themselves are collected using a magnet.
All operations are performed under continuous ultrasound exposure with a frequency of 22 kHz.
To expedite the process of obtaining composite replacement solution of ammonia to hydrazine hydrate (N2H4·H2O). Our studies showed that the choice of matrix are the best on the reproducibility of the results hold when using polyvinyl alcohol. The operation of the modification with glutaraldehyde in the proposed technical solution is excluded as unnecessary operation.
Thus, the proposed method is compared with the prototype has the following distinctive features:
1). The process of deposition of a mixture of sole is bivalent and trivalent iron and polyvinyl alcohol is carried out in vapor ammonia, but as the media reaction gas is an aqueous solution of ammonia (NH4OH) or hydrazine-hydrate (N2H4·H2O).
2). The operation of the modification with glutaraldehyde excluded.
The use of these distinctive features to achieve their goal, the authors are unknown.
It should be noted another advantage of using vapors of ammonia as a restorative environment. Use the vapors of ammonia allows the reaction recover successfully from a precursor in the liquid state and the gel state and in a state of powder.
Figure 1 presents the scheme of obtaining nanoparticles of magnetite by the proposed method in a desiccator with the prepared precursor using vapors of ammonia (NH4OH) or hydrazine-hydrate (N2H4·H2O). 1 - desiccator, 2 - table, 3 - Petri dish, 4 - precursor.
Figure 2 presents x-ray diffraction analysis of the obtained nanocomposites nanocomposite.
Example 1. In 150 ml of deionized water was dissolved 11,25 g FeCl3·6H2O and 4.61 in g FeCl2·4H2O. In the prepared solution was poured a solution of polyvinyl alcohol (10 ml) was dissolved 0.2 g of dry powder mixtures of PVA). Then, the solution was stirred until a homogeneous consistency.
Thus obtained precursor solution was poured in a Petri dish and services is enableval on the table holder desiccator (see 1). At the bottom of the table poured into about 300 ml of an aqueous solution of ammonia of 25%. The desiccator was closed and passed the day. By the end of the day the reaction products from the Petri dishes were thoroughly washed in deionized water, and the nanoparticles were collected by a magnet. Data mössbauer spectroscopy showed that the obtained nanoparticles are nanoparticles of Fe3O4in the super-paramagnetic state. The results of mössbauer spectroscopy was confirmed by the results of x-ray analysis (see Figure 2). According to transmission electron microscopy, as a result of the work were obtained nanoparticles of Fe3O4size 8-16 nm in a matrix of polyvinyl alcohol.
Example 2. In 150 ml of deionized water was dissolved 11,249, FeCl3·6N2Oh and br4.61 .FeCl2·4H2O. To the resulting solution was poured prepared solution of polyvinyl alcohol (10 ml) was dissolved 1 g of dry powder mixtures of PVA). Then, the solution was stirred until a homogeneous consistency.
The resulting precursor solution was poured in a Petri dish and set on the table the holder of the desiccator. At the bottom of the desiccator poured into about 100 ml. of hydrazine hydrate. The desiccator was closed and kept it as a Petri dish containing precursor 20 hours.
The reaction products from the Petri dishes were thoroughly washed in deionized water, and NAS the particles were collected by a magnet.
According to transmission electron microscopy, as a result of the work were obtained nanoparticles size 10-18 nm. The results of x-ray analysis allowed us to conclude that this is magnetite particles.
The method of obtaining the magnetite nanoparticles stabilized polyvinyl alcohol, including the production of magnetite in an alkaline medium a mixture of salts of divalent or trivalent iron and polyvinyl alcohol with a weight content in the initial mixture from 4 to 18 wt.%, dispersing, washing and conducting all operations under continuous ultrasound exposure, characterized in that the deposition process of the mixture of salts of divalent or trivalent iron and polyvinyl alcohol is carried out in a vapor of ammonia using an aqueous solution of ammonia (NH4OH) or hydrazine-hydrate (N2H4·H2O).
FIELD: chemistry.
SUBSTANCE: invention relates to obtaining biocompatible magnetic nano-particles and can be applied for therapeutic purposes, in particular, for fighting cancer. Method of obtaining nano-particles, including iron oxide and silicon-containing casing and having value of specific absorption rate (SAR) 10-40 W per g of Fe with field strength 4 kA/m and frequency of alternating magnetic field 100 kHz, contains the following stages: A1) preparation of composition of at least one iron-containing compound in at least one organic solvent; B1) heating of composition to temperature in range from 50°C to temperature 50°C lower than temperature of reaction of iron-containing compound according to stage C1 for minimal period 10 minutes; C1) heating composition to temperature between 200°C and 400°C; D1) purification of obtained particles; E1) suspending purified nano-particles in water or water acid solution; F1) addition of surface-active compound to water solution, obtained according to stage E1); G1) processing of water solution according to stage F1) by ultrasound; H1) purification of water dispersion of particles, obtained according to stage G1); I1) obtaining dispersion of particles according to stage H1) in mixture of solvent from water and water-mixable solvent; J1) addition of alkoxysilane into dispersion of particles in mixture of solvent according to stage I1); and K1) purification of particles.
EFFECT: invention makes it possible to obtain biocompatible magnetic particles with high value of specific absorption rate (SAR).
42 cl, 3 dwg, 9 ex
FIELD: chemistry.
SUBSTANCE: invention can be used in inorganic chemistry. In order to obtain a magnetoactive compound by oxidative condensation of an iron (II) salt solution, condensation is carried out in the presence of nitrosated lignosulphonates in conditions of exposure to a magnetic field.
EFFECT: invention speeds up synthesis and enables to obtain a magnetoactive compound with high relative magnetic susceptibility.
1 tbl, 22 ex
FIELD: medicine, pharmaceutics.
SUBSTANCE: invention refers to a magnetic system which has a structure containing magnetic nanosized particles of formula MIIMIII 2O4, wherein MII=Fe, Co, Ni, Zn, Mn; MIII=Fe, Cr, or maghemite which are functionalized by bifunctional compounds of formula R1-(CH2)n-R2 where n = 2-20, R1 is specified in: CONHOH, CONHOR, PO(OH)2, PO(OH)(OR), COOH, COOR, SH, SR; R2 is an external group, and is specified in: OH, NH2, COOH, COOR; R is an alkyl group or an alkaline metal specified in C1-6-alkyl and K, Na or Li, respectively). The structure also includes a polymer optionally containing a pharmacologically active molecule, and an external pharmacologically active molecule may be specified in anticancer agents, antimicrobial agents, anti-inflammatory agents, immunomodulators, molecules acting on the central nervous system or able to mark cells so as to enable the identification thereof by means of the usual diagnostic detectors. The invention also refers to a method for preparing the nanosized particles of formula MIIMIII 2O4 which consists in adding a metal salt to alcohol, heating to complete solubilisation of salts, adding water to facilitate salt hydrolysis and heating to temperature 150-180°C to prepare a suspension to be then functionalised. The invention also refers to a method for preparing the magnetic system, wherein the functionalised nanoparticles and the pharmacologically active molecules are integrated into the matrix of a water-insoluble polymer, and the prepared structure is continuously and one-stage coated with adequate surfactants.
EFFECT: invention aims at preparing the magnetic system suitable for hyperthermia procedures.
16 cl, 4 tbl, 1 dwg, 26 ex
FIELD: chemistry.
SUBSTANCE: invention can be used in chemical industry. Method of obtaining magnetoactive compound includes addition of nitrous acid salt to acidified solution of iron (II) salt, with further precipitation with alkali solution.
EFFECT: invention makes it possible to obtain magnetoactive iron compound with high relative magnetic susceptibility.
3 cl, 1 tbl, 57 ex
FIELD: chemistry.
SUBSTANCE: invention can be used in chemical industry. The method of producing magnetic liquid involves precipitation of finely dispersed magnetite from aqueous solutions of iron (II) and iron (III) salts in excess of iron (II) with ammonia solution, washing the precipitate with distilled water, simultaneous activation and stabilisation of the magnetite while heating with a mixture of acetic acid and a surfactant containing a fatty acid, washing the stabilised magnetite with distilled water and peptisation while heating in a carrier liquid based on vacuum oil. Peptisation is carried out for 4-6 hours immediately after washing the stabilised magnetite with distilled water. The surfactant used is oleic acid, the acetic acid used is glacial acetic acid and the vacuum oil used is mineral hydrocarbon oil.
EFFECT: invention improves the quality of the end product, simplifies the method, reduces power consumption and improves environmental safety of the process.
1 ex, 1 tbl
FIELD: chemistry.
SUBSTANCE: invention can be used in chemical industry. The method of producing magnetite with a developed surface involves preparation of iron (II) chloride and iron (III) nitrate solutions and draining the solutions of the obtained salts. Carbonyl iron is used to obtain the iron salts. Iron (III) nitrate is obtained by adding 50-60 ml of 3% hydrogen peroxide solution. A protective toluene film forms over the iron (II) chloride solution. The mixture of iron (II) chloride and iron (III) nitrate solutions is then precipitated with a solution which is prepared by pouring 1 litre of 25% ammonia solution to 8 litres of distilled water while stirring intensely.
EFFECT: invention increases specific surface area of magnetite to 130 m2/g.
1 ex
FIELD: chemistry.
SUBSTANCE: to obtain a magnetoactive compound, ligosulphonates first undergo nitrosation with sodium nitrite in an acidic medium and the magnetoactive compound is then deposited in the presence thereof. During nitrosation, the acidic medium is formed by adding an acid, preferably nitric acid.
EFFECT: invention increases magnetic susceptibility of the magnetoactive compound.
2 cl, 1 tbl, 19 ex
FIELD: process engineering.
SUBSTANCE: invention relates to chemistry and metallurgy and may be used in producing valuable products from red sludge. Sludge processing comprises the following stages: a) reducing at least a portion of iron oxide (III) and/or iron hydroxide (III) contained in red sludge by at least one-type reducer that contains at least one-type hydrocarbon; b) separating at least one solid phase of reaction mix from at least one liquid and/or gas phase. Note here that said one solid phase, and/or liquid phase, and/or gas phase contains one valuable products containing at least magnetite. Methane and/or natural gas and/or ethanol may be used as said reducer. Separated solid phase is separated into one first magnetising produc and one second non-magnetising product. The latter is use as at least additive to cement. At least one component produced from gas phase separated at stage b) is used as initial product for synthesis of hydrocarbons. In said synthesis, at least one component of red sludge is used to make a surfactant.
EFFECT: expanded applications.
16 cl, 4 ex
FIELD: chemistry.
SUBSTANCE: invention can be used in chemical industry. The method of producing magnetite using red mud formed during production of aluminium via the Bayer process, involves at least a step for reducing magnetite and/or goethite to magnetite via reduction at least once. The reducing agent contains at least vegetable oil and/or fat and/or coal together with at least vegetable oil and/or fat.
EFFECT: invention enables to recycle red mud and improves environmental friendliness of the process of producing magnetite.
12 cl, 4 ex
FIELD: medicine, pharmaceutics.
SUBSTANCE: invention can be used for creation of magnetic-susceptible sorbents applicable in medicine. A method for making magnetite nanoparticles stabilised by a biocompatible polymer having available functional formyl groups, involves preparation of magnetite of two mixed salts of ferrous iron and ferric iron adsorbed in polymeric matrixes, and modification of end groups of polymer. Magnetite is produced by coprecipitation in an alkaline medium of two mixed salts of ferrous iron and ferric iron, and at least one polymer selected from a number: chitosan, polyvinyl alcohol, block copolymer of polystyrene and polyethylene oxide. The weight relation of polymers in the composite makes 4 to 46 wt %. The produced composite is dispersed, processed in an aqueous solution of glutaraldehyde and washed. All the operations are combined with continuous ultrasound exposure.
EFFECT: invention allows producing multiuseable steady magnetite nanoparticles.
3 cl, 2 dwg, 1 tbl, 5 ex
FIELD: chemistry.
SUBSTANCE: invention can be used in electrochemical purification of sewage waters, which have complex composition of organic origin and a series of inorganic components. Electrochemical processing of sewage waters, which contain organic admixtures, is performed in anode chamber of two-chamber electrolyser under impact of asymmetric alternating current with density of 500 mA/dm2 with asymmetry 7-10 (ratio of negative half-cycle current density to density of positive half-cycle current Ik/Ia) and current frequency 1900-2200 Hz. After that, water is precipitated and/or centrifuged, and obtained sediment in form of suspension is washed and processed with toluene.
EFFECT: C60 clusters are obtained with minimal energy and financial expenditures.
FIELD: physics.
SUBSTANCE: invention relates to magnetic nanoelements. Magnetoresistive gradiometer head has a substrate with a dielectric layer on which there are four rows of thin-film magnetoresistive strips connected in series by low-resistance jumpers in each arm of a bridge circuit, said rows being connected into a bridge circuit by said jumpers, each of said strips having top and bottom protective layers with a ferromagnetic film in between, a first insulating layer on top of the thin-film magnetoresistive strips, on which is formed a first planar conductor with working parts, arranged over the thin-film magnetoresistive strips and a second insulating layer, a second planar conductor passing over and along the working thin-film magnetoresistive strip and a protective layer, wherein all thin-film magnetoresistive strips lie in one row, in all thin-film magnetoresistive strips the easy magnetisation axis of the ferromagnetic film is directed at an angle of 45° relative the longitudinal axis of the thin-film magnetoresistive strip, and the working arm of the bridge circuit closest to the edge of the gradiometre head is far from the three ballast arms of the bridge circuit, the width of the ballast thin-film magnetoresistive strip is N times smaller than the width of the working thin-film magnetoresistive strip, and the ballast row of the bridge circuit consists of a set of N parallel-connected thin-film magnetoresistive strips.
EFFECT: invention weakens the local magnetic field acting on a magnetoresistive gradiometer head and increases sensitivity.
2 cl, 3 dwg
FIELD: chemistry.
SUBSTANCE: invention relates to composite materials, particularly to metal matrix composites and can be used in making friction bearings. The metal matrix composite contains the following, wt %: antimony - 10.0-12.0, copper - 0.5-1.5, silicon carbide - 1.0-15.0, carbon nanotubes - 0.5-10.0, tin - the balance.
EFFECT: material has improved antifriction and mechanical properties and high temperature resistance in conditions where the friction pair operates with limited lubrication or short-term dry friction.
2 tbl
FIELD: chemistry.
SUBSTANCE: invention relates to transparent and colourless compositions which absorb infrared radiation. The composition contains binder which contains a radiation-curable composition and not more than 500 ppm, relative the total weight of the composition, of particles of non-stoichiometric tungsten oxide of general formula WO2.2-2.999 with average size of primary particles of not more than 300 nm, dispersed in the binder. Also described are films made from the infrared-radiation absorbing composition.
EFFECT: obtaining transparent and colourless compositions which absorb infrared radiation.
14 cl
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to production of monodisperse nano-sized powders with preset structures and properties. It can be used in pharmaceutical, food, textile industries, etc. Disperse substances are converted in liquid state by heating at temperature above melting point and below boiling point or that of dissolution in solvent. Obtained fluids are placed in vessel connected with emitted whereto fed is potential that ensures steady-state flow with uniform particles structure. Dispersing is performed in inert gas or fluid at temperature that allows conversion of dispersed flow into solid state. Note here that inert medium is displaced towards dispersed flow at the rate higher than that of particles dancing.
EFFECT: monodisperse homogeneous-composition powders.
4 cl
FIELD: medicine, pharmaceutics.
SUBSTANCE: present invention refers to pharmacology, nanomaterials and nanotechnology, and concerns a method for selective final purification of nanodiamonds to remove foreign nitrate ions and sulphur compounds to be used in pharmaceutics; the method implies that charge-free nanodiamond powder is treated with alkaline water of the concentration of 0.01-1 mole/l at 20-100°C; the prepared suspension is then decanted and centrifuged; the precipitation is washed with water using ultrasound, separated and dried.
EFFECT: higher effectiveness of the method.
5 cl, 1 dwg, 7 ex
FIELD: medicine, pharmaceutics.
SUBSTANCE: invention refers to medicine, particularly to pharmacology and pharmaceutics, and concerns a sedative agent representing glycine immobilised on detonation nanodiamond particles 2-10 nm in size, and to a method for preparing it.
EFFECT: preparing the sedative agent.
4 cl, 7 dwg, 13 tbl, 4 ex
FIELD: medicine, pharmaceutics.
SUBSTANCE: invention refers to pharmaceutics and medicine, and concerns an antihypoxant representing the amino acid glycine immobilised of detonation nanodiamond particle 2-10 nm in size, and to a method for preparing it.
EFFECT: agent exhibits low toxicity and high efficacy.
4 cl, 5 dwg, 8 tbl, 3 ex
FIELD: instrumentation.
SUBSTANCE: probe for scanning probe microscope comprises charge sensor arranged at cantilever tip and composed of single-electrode transistor made in silicon layer doped to degenerate state of silicon-on-insulator (SOI) structure on substrate. Transistor has two feed electrodes arranged at acute angle to each other in substrate plate with converging ends staying in contact with transistor feed island to make transistor source and drain, two sharpened mid electrode arranged in the area of convergence of feed electrodes, its tip being directed towards conducting island to make capacitance clearance with the latter acting as transistor gate. Jumpers in zone of contact of feed electrode ends with transistor feed island represent resistor elements to make tunnel transition. Note here that substrate edge is skewed while transistor island, jumpers and feed and mid electrode ends adjoining said skew extend beyond the insulator layer.
EFFECT: ruled out parasitic noise effects of moving charges concentrated in SOI plate insulator layer, higher charge sensitivity of probe.
5 cl, 6 dwg
FIELD: metallurgy.
SUBSTANCE: modified powder of zinc oxide is obtained by sedimentation from salt solution. Obtained powder is treated in polymer diluted solution in non-polar solvent. Then heat treatment is performed for obtained cover polymerisation.
EFFECT: increasing ultimate tensile strength and building sealers deformation degree.
6 dwg, 2 tbl, 1 ex
FIELD: chemistry.
SUBSTANCE: invention relates to field of catalysis. Described is catalyst for recycling heavy oil fractions, in which active component, selected from nickel, or cobalt, or molybdenum, or tungsten compounds, or any their combination, is applied on inorganic porous carrier, consisting of aluminium oxide, dioxides of silicon, titanium or zirconium, alumosilicates or iron silicates, or any their combination, characterised by the fact that said catalyst contains macrospores, which form regular spatial macropore structure, and portion of macropores with size more than 50 nm constitutes not less than 30% in total specific volume of said catalyst pores.
EFFECT: increase of catalyst activity.
4 cl, 3 dwg, 1 tbl, 7 ex
