Method of receiving of nano-crystalline calcium hydroxyapatite
SUBSTANCE: invention relates to method of receiving of nano-crystalline hydroxyapatite. According to the invention calcium nano-crystalline hydroxyapatite is received by interaction of compound of calcium and ammonium hydro-phosphate. In the capacity of calcium compound it is used sugar lime C12H22-2nO11Can, at n, which is situated in the range from 0.5 up to 2. Particles size of the received hydroxyapatite is 30-50 nm.
EFFECT: receiving of nano-crystalline powder of calcium hydroxyapatite, which contains unaggressive biocompatible accompaniment of the reaction and that provides its usage in medicine.
3 dwg, 1 tbl, 1 ex
The invention relates to methods for producing powders of calcium hydroxyapatite (HAP), which can be used in medicine.
Known methods for producing gap, in which the starting compounds using ammonium phosphate and calcium nitrate (1) or ammonium phosphate and calcium chloride (2). The disadvantages of these methods is the inability to completely remove a byproduct ammonium nitrate or ammonium chloride by washing, which makes this powder is corrosive to body tissues when used as a filler for bone defects or as a carrier of drugs.
A method of obtaining gap, in which the starting components used calcium chloride and sodium phosphate (3). The disadvantage of this method is the use of boiling in alkali, which results in coarse powder.
Closest to the proposed invention is a method (4) receipt of HAP powder that does not contain corrosive by-product credits, in which the starting compounds used calcium oxide and ammonium phosphate. The disadvantage of this method is to obtain coarse powder gap, which is caused by the synthesis of the interaction of components in the solid phase, as well as the use of high temperature is processing at high (950°C) temperature.
The aim of the present invention was to obtain nanocrystalline HAP powder containing biocompatible non-aggressive co-product of the reaction.
In a method of producing nanocrystalline HAP powder as starting compounds used saharat calcium12H22-nAbout11CAnand ammonium phosphate.
The solution saharat calcium is prepared by the interaction calcined at 1000°C the oxide of calcium and sucrose solution according to reaction (1).
The value of n for this reaction range from 0.5 to 2. Lower values of n lead to a significant increase in the number of sucrose to conduct synthesis without significant effect on the particle size of the product. For n greater than 2, in solution form insoluble saharty calcium, while carrying out the synthesis of the gap leads to the formation of multiphase product, containing, along with the gap unreacted source component - saharat calcium.
To the obtained saharat calcium added dropwise a solution of ammonium hydrogen phosphate with constant stirring at room temperature in accordance with reaction (2).
Then transform the obtained gel of amorphous calcium phosphate in suspension NANOKRISTALLIChESKOGO gap the reaction mixture is heated up to T=60°C. the Obtained suspe is the Zia filter, the filter cake is dried in a thin layer.
According to x-ray analysis of the powder contains nanocrystalline HAP powder (Figures 1-3). The particle size of the gap is 30-50 nm.
The invention is illustrated in the figures and example.
Figure 1. Data of x-ray phase analysis for the powder synthesized from ammonium hydrogen phosphate and saharat calcium C12H21O11Ca0.5.
Figure 2. Data of x-ray phase analysis for the powder synthesized from ammonium hydrogen phosphate and saharat calcium12H20About11Sa (Example).
Figure 3. Data of x-ray phase analysis for the powder synthesized from ammonium hydrogen phosphate and saharat calcium C12H18O11Ca2.
To 28,04 g pre-calcined at 1000°C Cao was added to 1 l of an aqueous solution of sucrose in which it was contained 171,05, the ratio of calcium oxide and sucrose produces a clear solution adenocarcinoma (n=1) saharat C12H20O11Ca. To the resulting solution saharat, having a pH of at least 12 was added dropwise 0.5 m solution of ammonium hydrogen phosphate. Interaction according to reaction (3) resulted in the formation of a stable gel, and after heating to 60°With the formation of stable to sedimentation of suspensions of nanocrystalline HAP in rasterisers.
Data of x-ray phase analysis confirm the formation of nanocrystalline HAP with a particle size of 30-50 nm.
Similarly, were synthesized powders NANOKRISTALLIChESKOGO gap from saharat calcium hydrogen phosphate and ammonium when changing n from 0.5 to 2 (table). The table shows that with these changes the values of n in the saharat calcium C12H22-2nO11Canwhen performing synthesis on the proposed method formed nanokristallichesky gap with particle size of 30-50 nm. The byproduct of the reaction is saharat ammonium decompose ammonia and sucrose. Sucrose is a substance not corrosive to body tissues.
|No.||The value n in the saharat calcium C12H22-2nO11Can||The particle size of the gap||The phase composition of the target product||Shapes|
|1||0,5||30-50 nm||100% hydroxyapatite||1|
|2||1,0||30-50 nm||100% hydroxyapatite||2|
|3||2,0||30-50 nm||100% hydroxyapatite||3|
Thus, the experimental data show that the use of the claimed method allows to obtain nanocrystalline HAP powder that does not contain corrosive to tissues of a living organism byproduct.
1. Vasilikou, Iperu, Vaikasi, Namechina, Maagazine, Sycheva VY Patent RU 2038293, 26.06.1992. The method of obtaining hydroxyapatite.
2. Astaman, Oueration, Grabelnikova, Timetrack, Genealogia, Limasexadriana. Copyright certificate 710928. 25.01.1980. The method of obtaining calcium hydroxylapatite.
3. Ulitize, Sdhedule, Spiglazova and Aggripina. Inventor's certificate SU 1450852, 07.01.1987. A method of producing a sorbent-hydroxyapatite.
4. Vpolicy, Havronicheva, Gaiola, Gesheva, Emoval and Namerow. Patent SU 1834836, 26.11.1991. The method of obtaining calcium hydroxylapatite.
The method of obtaining nanocrystalline hydroxyapatite calcium interaction calcium hydrogen phosphate and ammonium, wherein as calcium use saharat calcium C12H22-2nO11Canwhen n, lying is m in the interval from 0.5 to 2.
FIELD: medicine, pharmaceutics.
SUBSTANCE: it is described a nanopatterned calcium phosphate material on the basis of threecalciumphosphate-hydroxyapatite system for reconstruction of osteal defects. The invention concerns to the calcium phosphate ceramic materials intended for manufacturing of osteal implants and-or replacement of defects at various osteal pathologies. The material on the chemical compound is close to a natural osteal tissue (the structure corresponds to the threecalciumphosphate-hydroxyapatite system). The unique ultradisperse structure of a material is formed at the expense of use of initial calcium phosphate nanopatterned powders and the additive.
EFFECT: reception of a ceramic material with uniform structure with the average size of particles less than 100 nanometres.
1 tbl, 3 ex
SUBSTANCE: method of phosphate ore processing includes one-step counterflow process of phosphate ore decomposition, characterised by P2O5 content exceeding 20% in weight, by processing it with water solution of hydrochloric acid, which has HCl concentration lower than 10% in weight, with formation of processing solution, consisting of water phase, in which calcium phosphate is in dissolved state, and of solid phase, which contains admixtures; preliminary neutralisation of processing solution, containing calcium phosphate in solution, to first pH value, which is lower than pH value, at which essential part of said dissolved calcium phosphate precipitates in form of calcium monohydrophosphate (DCP), with precipitation of admixtures; first separation of insoluble solid phase and water phase of processing solution; repeated neutralisation of water phase obtained during first separation to second pH value, exceeding said first pH value, with DCP precipitation; and second separation of repeatedly neutralised water medium, which represents water solution of calcium chloride and precipitated DCP.
EFFECT: method allows optimising ratio between dissolved P2O5 output and purity degree of final product and ensure economically profitable process, which can be realised on simple equipment.
14 cl, 3 dwg, 2 tbl, 1 ex
SUBSTANCE: nano-sized highly-pure hydroxylapatite (HAP) is obtained in form of alcohol colloid solution (gel), which can be used for production of medicinal preventive preparations in stomatology, for applying bioactive coating on bone implants. Method includes hydroxylapatite synthesis by adding solution of orthophosphoric acid to calcium hydroxide solution and exposure to ultrasound impact, and ethyl or isopropyl alcohol is added to colloid of highly-pure nano-sized hydroxylapatite with concentration from 5% to 40±2% in order to obtain concentration of hydrooxylapatite in alcohol from 0.2 to 20%. After that alcohol mixture is processed with ultrasound with frequency 10-50 kHz during 1-2 hours.
EFFECT: alcohol colloid of nano-sized hydroxylapatite with high stability.
2 cl, 3 ex
SUBSTANCE: invention relates to technology of obtaining inorganic materials, namely to methods of obtaining nanosized highly pure hydroxylapatite (HAP) in form of colloid solution or gel, which can be used for production of medico-preventive preparations for stomatology, for application on bone implants. Method of obtaining nanosized colloid hydroxylapatite includes synthesis of hydroxylapatite in saturated solution of calcium hydroxide, decanted after 24-hour settling from sedimented aggregates Ca(OH)2, by adding at rate 1.5-2.2 ml/min per litre of alkali solution 10-20% solution of orthophosphoric acid with constant mixing until pH value of reaction mixture is not lower than 10.5±0.5. Mixture is mixed during 20-30 minutes, settled during 1-2 hours and decanted until liquid phase stops forming on the surface. Obtain product represents colloid solution of highly pure hydroxylapatite with concentration 1.5-2%. Increase of hydroxylapatite concentration within the range from 2 to 30% is carried out by evaporation at temperature not higher than 60°C, and for obtaining nanosized hydroxylapatite with concentration 40±2% initial colloid solution is subjected to complete freezing with further unfreezing at temperature not more than 60°C and liquid phase decanting.
EFFECT: obtaining stable product with set in advance concentration, possessing higher penetrating ability and biochemical activity.
3 cl, 4 ex
SUBSTANCE: method of processing of residual products containing phosphoric acid to calcium phosphates comprises its mixing with calcium-containing compounds, separation of derived slurry with filtration and drying. The limestone is used as calcium-containing compound, initially it is fed for mixing in quantity necessary for monocalcium phosphate, then derived slurry is divided to two flows in ratio 1:(1.5-4), the major flow is mixed with lime taken in quantity necessary for dicalcium phosphate formation, derived slurry is separated with filtration and minor flow of monocalcium phosphate slurry is added to separated dicalcium phosphate before drying and granulating. Preparation of monocalcium phosphate slurry is carried out in two stages, at first stage the phosphoric acid is mixed with limestone up to mixture pH =2.9-3.1, at second stage - up to mixture pH =3.5-3.7, during mixing of monocalcium phosphate slurry with lime pH is maintained in the range 5.4-5.6. Drying and granulating are carried out at the same time in drum granulator-dryer.
EFFECT: method enables to process the residual products to granulated calcium phosphates with usage the lowest-cost raw materials.
3 cl, 1 tbl, 1 ex
FIELD: paint and varnish industry.
SUBSTANCE: anticorrosive pigment comprises , in mass per cents, 3.0-4.7 of calcium chromate and waterless dicalciumphosphate as the balance.
EFFECT: improved anticorrosion capabilities.
FIELD: production of pure phosphoric acid and calcium monohydrophosphate.
SUBSTANCE: proposed method includes decomposition of phosphate ore by first hydrochloric acid solution at concentration not exceeding 10 mass-%, separation of liquid decomposition product into insoluble solid phase containing admixtures and separate aqueous phase containing phosphate, chloride and calcium ions in form of solution, neutralization of aqueous phase separated from liquid decomposition product by adding calcium compound for obtaining insoluble settled-out calcium phosphate by means of phosphate ions, separation of neutralized aqueous phase into aqueous phase containing calcium and chloride ions in form of solution and settled solid phase on base of water-insoluble calcium phosphate and dissolving of at least part of separated settled solid phase in second aqueous hydrochloric acid solution containing hydrochloric acid in the amount exceeding its content in first hydrochloric acid solution, thus forming aqueous solution containing phosphate, chloride and calcium ions extracted by organic extracting agent at extraction in "liquid-liquid" system. Proposed method makes it possible to avoid fine grinding or roasting of ore.
EFFECT: enhanced efficiency of extraction for production of pure concentrated phosphoric acid solution with no contamination of surrounding medium.
24 cl, 2 dwg, 1 tbl, 4 ex
FIELD: inorganic chemistry, chemical technology.
SUBSTANCE: invention relates to technology for preparing fodder calcium phosphates, namely to producing monocalcium phosphate. Method involves mixing wet-process phosphoric acid with a calcium-containing component in the presence of recycle, granulation and drying the product. Mixing process is carried out for two stages. At the first stage wet-process phosphoric acid with the concentration 62-65% of P2O5 is fed and process is carried out at recycle index = 1:(0.3-0.5) up to decomposition degree of calcium-containing raw = 0.89-0.92 at this stage. The second stage is combined with granulation and carried out its in high-speed mixer in water addition to obtain moisture in mixture 9.5-13%. The rate and time for mixing are regulated to provide the decomposition degree of calcium-containing raw = 0.93-0.99, and temperature at the next drying stage is maintained in the level 105-115°C. Method provides simplifying the process, reducing energy consumption and preparing product with the high content of P2O5 in water-soluble form and low content of fluorine.
EFFECT: improved method for preparing.
2 cl, 3 ex
FIELD: industrial inorganic synthesis.
SUBSTANCE: monocalcium phosphate, widely applied in agriculture, is prepared by mixing extraction phosphoric acid with calcium-containing component followed by granulation and drying of product. During mixing of components, appropriate temperature and moisture are maintained to ensure viscosity of mixture 3-7 mPa*s, and granulation and drying are carried out simultaneously in drum-type granulator drier. Calcium-containing component is either calcium carbonate or mixture thereof with limestone, whose does not exceed 15% of total weight of calcium-containing raw material. Moisture content in worked out drying agent leaving drum-type granulator drier equals 70-80 g per 1 kg dry air.
EFFECT: simplified process flowsheet, enabled granule size control, and increased strength of granules.
3 cl, 3 ex
SUBSTANCE: invention relates to micro system hardware, and can be used in producing sensors based on tunnel effect to convert displacement into electric signal in monitoring data processing systems that serve to forecast, diagnose and control the effects of impact waves and acoustic oscillations exerted onto various structures, vehicles, industrial buildings and structures, as well as to control temperature, develop supersensitive mikes and medicine hardware. In compliance with this invention, the sensor cantilever electrode represents a bimorph beam made up of consecutively formed layers differing in thermal expansion factors. Note that the lower layer thermal expansion factor is lower as compared with that of the upper layer. Note also that the tunnel electrode represents a bundle of nanotubes. The proposed nanosensor incorporates thin-film heater to allow desorption of low-molecular substances, precision alignment of tunnel gap and formation of nanotubes after removal of "sacrificial" service layer.
EFFECT: increased sensitivity, vibro- and impact resistance, manufacturability and reproducibility, lower costs of manufacture.
2 cl, 3 dwg
SUBSTANCE: two fullerenes 1 C20 are put into a closed carbon nanotube 2, at the opposite end of which there is spherical fullerene 3 C60, acting as a plunger, applying a pressure of 43.24 hPa on two fullerenes 1 C20.
EFFECT: obtaining dimers of fullerene C20 without impurity atoms.
3 dwg, 1 tbl
FIELD: chemistry; photographic industry.
SUBSTANCE: invention relates to photographic industry, particularly to technology of silver-halide photographic emulsion preparation. According to the invention the production of photographic emulsion based on silver-halide laminate microcrystals (LMC) with epitaxial nanostructures is started from preparing nuclear emulsion from solution of AgNO3 and KBr. Thereafter, substrate LMC AgBr are derived by adding solution of AgNO3 and KBr in the nuclear emulsion. Annular epitaxial nanostructures containing AgBr/AgCl are formed on the produced LMC AgBr by adding Kl and KCl solutions in reaction mixture. At the final stage, firstly, epitaxial nanostructures are converted by adding solution of KBr into reaction mixture, thereafter the second conversion is carried out by adding small particle emulsion prepared separately and containing AgBr0.98l0.02-AgBr0.90I0.10.
EFFECT: simplification of photographic emulsion preparation with optimal photographic characteristics of light sensitivity, as well as microcrystal dispersion characteristics used in industrially produced photomaterials.
1 cl, 1 tbl, 14 ex
SUBSTANCE: invention relates to nanotechnology and nanostructures, particularly carbon-base materials and can be used in different field of engineering and energetics. In vacuum on substrate made of dielectric material it is sediment evaporated in vacuum silver by means of plasma carbon-base material. Silver sedimentation is implemented before the sedimentation of carbon-base material. Evaporation of carbon-base material, in the capacity of which it is used graphite, is implemented by pulsed arc discharge. Plasma for sedimentation of carbon-base material is created outside the discharge gap area of voltaic arc in the form of compensated currentless for-coagulates of carbonaceous plasma with density 5-1012-1·1013 cm-3, duration 200-600 mcs, recurrence rate 1-5 Hz. During the sedimentation process of carbon-base material it is implemented stimulating effect of carbonaceous plasma by inert gas in the form of ion flow with energy 150-2000 eV, which is directed perpendicularly to carbonaceous plasma stream. Then substrate with sediment on it silver and carbon-base material is extracted from vacuum chamber and annealed on air at temperature 400°C during 10 minutes.
EFFECT: it is manufactured carbon-base material, containing metal, with new properties, for instance electrical conductance and transparency.
FIELD: production processes.
SUBSTANCE: invention refers to obtaining of wear-resisting ultra-hard coatings, namely, to forming of diamond-type coatings and can be used in metalworking, engineering industry, nanotechnologies, medicine and electronics. Preliminary there performed is product surface plasma stripping by accelerated ions in vacuum chamber at pressure of 10-3 - 10 Pa. Then adhesion layer is applied by plasma method. The thickness is 1-500 nm. The layer is made from metal that belongs to the group of aluminium, chrome, zirconium, titanium, germanium or silicone or their alloys. At the same time the product receives direct or pulse negative voltage of 1-1500 V. Then there applied is intermediate layer with thickness of 1-500 nm. It consists of carbon and metal mixture. Metal belongs to the group of aluminium, chrome, zirconium, titanium, germanium or silicone or their alloys. Intermediate layer is applied at ascending changing of carbon concentration in this mixture from 5 to 95 at.%. At the same time the product receives direct or pulse negative voltage of 1-1500 V. Then there applied is at least one layer of carbon diamond-type film by graphite cathode or laser spraying or by plasma destruction of carbon-bearing gases or carbon-bearing liquid vapours.
EFFECT: increase of adhesion, wear resistance and temperature stability of diamond-type coating.
11 cl, 1 dwg, 5 ex
SUBSTANCE: invention relates to metallurgy field and can be used for manufacturing of high-duty cast iron with globular graphite. For receiving of magnesium-bearing nano- modifying agent is blended with water solution of polyvinyl alcohol, chloride of magnesium and iron in molar correlation (10-5):1:1, agreeably, it is evaporated specified mixture before gel formation after what it is implemented carbonation at temperature 350-500°C in atmosphere of inert gas with formation of carbon nanotube, filled by chloride of magnesium and iron.
EFFECT: invention decrease magnesium losses 1,5-2 times with introduction of nano- modifying agents into the cast iron.
6 ex, 1 tbl, 6 dwg
SUBSTANCE: invention can be used at production of finishing compositions, film coatings, radiation-resistant materials. The diamond-carbon material contains the carbon in the form of diamond cubic modification and the X-ray amorphous phase in the mass ratio (40-80):(60-20) respectively; the content of said material is as follows (wt %): carbon 89.1-95.2; hydrogen 1.2-5.0; nitrogen 2.1-4.8; oxygen 0.1-4.7; non-combustible admixtures 1.4-4.8. This material is obtained in enclosed volume, in the gas phase inert to carbon by the detonation of carbon-containing explosive with oxygen deficiency placed into the shell of deoxidant-containing condensed phase with deoxidant/carbon-containing explosive mass ratio not less than 0.01:1. The samples of the obtained diamond-carbon material are prepared for elemental analysis by exposition at 120-140°C under vacuum 0.01-10.0 Pa during 3-5 hrs and following treatment at 1050-1200°C by the oxygen flow with the rate providing their combustion during 40-50 s.
EFFECT: invention allows to obtain the product with high carbon content, predictable properties and ultimate composition in the desired phase state.
4 cl, 1 tbl, 25 ex
SUBSTANCE: invention refers to the catalytic systems based on gold; usage of nanometric gold precipitation by the condensation from vapour phase to the activated carrier; system of breathing organs defence using aforesaid catalytic systems. The method of heterogenous catalytic system making is described including: 1) condensation from vapour phase of the catalytically active gold clusters with dimensions in the range from 0.5 to 50 nm to the nanoporous carrier; 2) the following stages: (a) impregnation of water-soluble salt to the catalyst nanoporous carrier; (b) thermic treatment of the said impregnated carrier at temperature more than approximately 200°C; (c) condensation from vapour phase of the catalytically active gold clusters with dimensions in the range from 0.5 to 50 nm to the said thermically treated nanoporous carrier; 3) following stages: a) aggregation of the relatively small particles multifold and of the relatively large particles multifold to the multifold of nanoporous composite particles; b) precipitation of catalytically active gold clusters with dimensions in the range from 0.5 to 50 nm gold clusters to the said composite particles by the condensation from vapour phase. The described heterogenous catalytic system contain: 1) nanoporous carrier; at least one water-soluble salt impregnated to the said carrier; clusters of catalytically active gold with dimensions in the range from 0.5 to 50 nm precipitated on the said carrier with the penetration depth index in the range from ca 1×10-9 to ca 0.1; 2) multifold of the composite catalytically active particles characterised in that said catalytically active particles are obtained from the components containing relatively small particles and relatively large particles with said composite particles containing catalytically active gold precipitated on the relatively small particles by the condensation from vapour phase. The system of breathing organs defence including any of aforesaid heterogenous catalytic systems is described.
EFFECT: invention provides essential improvement of the method of gold-containing catalytic systems preparation and enhancing of their characteristics.
22 cl, 71 ex, 4 tbl, 58 dwg
SUBSTANCE: invention is related to micro- and nanoelectronics and may be used in production of integral silicon chemical and biosensors for automated control of environment, in ecology, in chemical production, in biology and medicine. Invention is aimed at reduction of nanosensor size, reduction of defectiveness, increased sensitivity, repeatability and efficiency, achievement of compatibility with standard industrial technology VLSI. In method for manufacture of nanosensor, which consists in the fact that dielectric layer is created on silicon substrate, and on surface of dielectric layer silicon layer is formed, from which nanowire with ohm contacts is formed via mask by etching, etching for formation of nanowire with ohm contacts of specified size is carried out in vapours of xenon difluoride with the rate of 36÷100 nm/min, at temperature of 5÷20°C, for 0.3÷1.3 min., silicon layer, from which nanowire is formed with ohm contacts by etching, is created with thickness of 11÷45 nm, and etching mask used is mask of polymer polymethyl methacrylate with thickness of 50÷150 nm.
EFFECT: reduction of nanosensor size, reduction of defectiveness, increased sensitivity, repeatability and efficiency, achievement of compatibility with standard industrial technology VLSI.
FIELD: physics, semiconductors.
SUBSTANCE: invention is related to methods for creation of metal nanowires on surface of semiconductor substrates and may be used in creation of solid-state electronic instruments. Substance of invention: in method for creation of conducting nanowires on surface of semiconductor substrates, copper is deposited on surface of silicon Si(lll) with formation of buffer layer of copper silicide Cu2Si at the temperature of 500°C under conditions of ultrahigh vacuum. Buffer layer of copper silicide is formed with monatomic thickness, afterwards at temperature of 20°C at least 10 layers of copper are deposited on atomic steps of buffer layer surface, which form nanowires of epitaxial copper that are oriented along atomic steps of substrate.
EFFECT: provides for creation of nanowires that possess high conductivity, with the possibility of these nanowires formation location control.
FIELD: carbon materials.
SUBSTANCE: weighed quantity of diamonds with average particle size 4 nm are placed into press mold and compacted into tablet. Tablet is then placed into vacuum chamber as target. The latter is evacuated and after introduction of cushion gas, target is cooled to -100оС and kept until its mass increases by a factor of 2-4. Direct voltage is then applied to electrodes of vacuum chamber and target is exposed to pulse laser emission with power providing heating of particles not higher than 900оС. Atomized target material form microfibers between electrodes. In order to reduce fragility of microfibers, vapors of nonionic-type polymer, e.g. polyvinyl alcohol, polyvinylbutyral or polyacrylamide, are added into chamber to pressure 10-2 to 10-4 gauge atm immediately after laser irradiation. Resulting microfibers have diamond structure and content of non-diamond phase therein does not exceed 6.22%.
EFFECT: increased proportion of diamond structure in product and increased its storage stability.