Method to manufacture highly stable pressure sensor based on thin-film nano- and microelectromechanical system

FIELD: measurement equipment.

SUBSTANCE: method to manufacture a highly stable pressure sensor based on thin-film nano- and microelectric systems (NiMEMS) consists in the fact that after connection of output conductors to contact sites prior to sealing of strain-elements with links and contact sites, they are exposed until total perception to test lower and higher temperatures, values of which by absolute values are accordingly equal to at least maximum permissible lower and higher temperature in process of sensor operation. Resistances of strain resistors are measured under acting temperatures. Temperature coefficients of strain resistors are determined in the range of acting temperatures. On their basis they calculate the criterion of time stability according to the ratio Ψτα=(R2α2R4α4-R1α1R2α3)(R2α)-1, where R1, R2, R3, R4 - resistance of accordingly the first, second, third, fourth strain resistor of NiMEMS under normal climatic conditions; α1, α2, α3, α4 - temperature coefficient of resistance of accordingly the first, second, third, fourth strain resistor of NiMEMS; R=0.25(R1+R2+R3+R4); α=0.25(α1234). If ΨταταΔ where ΨταΔ - limit permissible value of time stability criterion, which is determined experimentally by statistical data for a specific dimension type of the sensor, than this assembly is written off as process scrap.

EFFECT: method improvement.

2 dwg

 

The present invention relates to measurement techniques, in particular a strain of the pressure sensors based on thin-film nano - and microelectricity systems with a bridge measuring circuit designed for use in control systems, control and diagnostics technically complex objects of long-term performance.

A known method of manufacturing a pressure sensor based on thin-film nano - and microelectrical system (Nimes)intended for use in control systems, control and diagnostics technically complex objects prolonged operation, which consists in polishing the surface of the membrane, applied to the dielectric, forming thereon testcustomerapi schema, joining contact pads to the elastic element and the connection of contact pads to the contact pads testcustomerapi scheme, in which prior to application of the dielectric is made of a dielectric sleeve directly in the recess of the elastic element, the polished surface of the membrane simultaneously with the polishing of the end face of the sleeve, then put dielectric on the membrane elastic element and the end face of the sleeve and form tensoku on the dielectric membrane and the bushing [1].

The disadvantage of this method of manufacture is relatively large temporary nest the mobility due to various forms of circumferential and radial strain gages, included in the opposite shoulders of the bridge measuring circuit. This is due to the fact that different forms of strain gages leads to different temporary change of the resistance of these strain gages, including due to the different rate of degradation and relaxation processes in circumferential and radial strain gages.

A known method of manufacturing a pressure sensor based on thin-film Nimes intended for use in control systems, control and diagnostics technically complex objects prolonged operation, which consists in polishing the surface of the membrane, forming therein a dielectric film and tensometric elements with low resistance vias and pads between them using the template testcustomermap layer having the configuration of a tensometric elements in areas shared with low resistance vias and pads, in the form of strips, including images of tensometric elements, and their continuation in two opposite directions, and in areas shared with pads, partially coinciding with the configuration of the pads and remote from the strips plots, attaching lead wires to the contact pads in areas remote from the strips plots [2].

The disadvantage of this method of manufacture is against the positive low temporal stability due to the lack of detection in the early stages of making a potentially unstable Nimes. The absence of such detection during operation leads to different temporary change in resistance of the strain gages Nimes, including due to the different rate of degradation and relaxation processes in the strain gages included in the opposite shoulders of the bridge measuring circuit. Insufficient temporal stability leads to an increase in the time the error and reduce resource and service life of the sensor.

The aim of the invention is to increase the temporal stability, resource, service life by identifying at an early stage of manufacture potentially unstable Nimes, providing the pass for the further Assembly of the strain gauges with the same (within the selected criterion) a temporary change in resistance, including from the same speed degradation and relaxation processes in the strain gages included in the opposite shoulders of the bridge measuring circuit.

This objective is achieved in that in the method of manufacturing a pressure sensor based on thin-film Nimes, which consists in polishing the surface of the membrane, forming therein a dielectric film and tensometric elements with low resistance vias and pads between them using the template testcustomermap layer having the configuration of tensol the cops in areas combine with low resistance vias and pads, in the form of strips, including images of tensometric elements, and their continuation in two opposite directions, and in areas shared with pads, partially coinciding with the configuration of the pads and remote from the strips plots, attaching lead wires to the contact pads in areas remote from the strips of sites, in accordance with the claimed invention, after attaching lead wires to the contact pads to seal tensometric elements with jumper wires and pads are subjected to exposure to full their perception test low and high temperatures, the values of which absolute values are respectively equal to not less than the maximum low and high temperature during operation of the sensor, measure the resistance of the strain gauges when acting temperatures determine the temperature coefficients of the resistances of the strain gages in the operating temperature range, calculate the criterion of temporal stability ratio

Ψtα=(R2α2R4α4-R1 1R3α3)(R2α)-1,(1)

where R1, R2, R3, R4- resistance respectively of the first, second, third, fourth strain gauge Nimes in normal climatic conditions; α1α2α3α4- temperature coefficient of resistance, respectively, first, second, third, fourth strain gauge Nimes; R=0,25(R1+R2+R3+R4); α=0,25(α1234), and if ΨtheταΔwhere ΨταΔ- the maximum permissible value of time stability criterion, which is determined experimentally according to the statistics for a specific size of the sensor, then this Assembly write in technological waste.

The inventive method is implemented as follows. Made (for example, from an alloy NECHTY) membrane with a peripheral base in the form of shells of revolution blade methods of treatment using the last stages of electric discharge machining. Polish the surface of the membrane using electrochimica-mechanical lapping and polirom the diamond lapping and polishing. Methods thin-film technology on the planar surface of the membrane sequentially applied as a continuous layer dielectric film in the form of patterns SiO-SiO2with a sublayer of chromium, testcustomer film (for example, from an alloy HNU). When forming the jumper and pads by photolithography low-resistance film (for example, from gold 3 l 999,9 m) sublayer (vanadium) is applied as a continuous layer on testcustomer film (alloy HNU). Form jumpers and pads by photolithography using a template jumpers and pads. The formation of bridges and pads can be mask method. In this case, the low-resistance film is a continuous layer is not applied, and is deposited through the mask.

The formation of tensometric elements carried out by a photolithography method using ion-chemical etching in argon and template testcustomermap layer having the configuration of a tensometric elements in areas shared with low resistance vias and pads, in the form of strips, including images of tensometric elements, and their continuation in two opposite directions, and in areas shared with pads, partially coinciding with the configuration of the pads and remote from the strips plots. After joining lead, launched the s to the contact pads to seal tensometric elements with jumpers and pads put elastic elements formed on them by the strain gages in a special technological device, providing protection from environmental and electrical contact with the use of welding lead wires from the measuring circuit, is subjected to the impact resistance strain gages to complete their perception test low and high temperatures, the values of which absolute values are respectively equal to not less than the maximum low and high temperature during operation of the sensor. For example, if the maximum low temperature of minus 150°C, the strain gages are subjected to temperatures of minus 150°C in the presence of high-precision equipment for the job such temperature. In the absence of such equipment would the strain gages to expose to the temperature of liquid nitrogen (minus 196°C). Measure the resistance of the strain gauges when acting temperatures. However due to the characteristic features of thin-film strain gauges their resistance depends not only on temperature but also on the deformation state. Determine the temperature coefficients of the resistances of the strain gages in the operating temperature range by the formula

αj=(Rj+-Rj-)R j--1,(2)

where αj- temperature coefficient of resistance of the j-th of the strain gauge Nimes; Rj+the resistance of the j-th of the strain gauge at the elevated temperature; Rj-the resistance of the j-th of the strain gauge at the lower temperature.

Compute certain temperature coefficients of resistance of the strain gages time stability criterion Ψtheratio (1), and if ΨtheταΔthen this Assembly write in technological waste. If ΨtheταΔthen this Assembly is removed from the fixture and after carrying out the necessary operations seal.

To establish causation of the claimed features and technical effect achieved will describe the most common elements of thin-film strain gages used to create Nimas. Analysis of the known solutions have shown that these elements can include thin-film elements, depicted in figure 1: dielectric 1, piezoresistive 2, the adhesive 3, pin 4, and the corresponding transitions between these elements.

The purpose of these elements is clear from their names. The thin-film elements ten is resistores, affecting the stability, it is necessary to refer also thin-film conductive elements. Figure 1 is a ratio between thicknesses of the thin-film elements and wedges etching conventionally not shown. Conductive elements of the strain gages are connected in series with the contact elements and are used to connect the strain gages in a bridge measuring circuit and the supply circuit and signal conditioning. From the point of view of stability we will consider only the conductive elements are in the areas of the contact elements to the nodes of the bridge measuring circuit. Typically, these nodes coincide with the places of joining lead wires connecting the bridge circuit to the power circuit and signal conversion. When performing Nimes with measuring bridge circuit of four working strain gages, as shown in figure 2, in the absence of elements of thermal compensation of the output signal Nimes in stationary temperature will be equal to

U=E(R4R3+R4-R1R1+R2),(3)

where E is the supply voltage of the bridge measuring circuit; R1, R2, R3, R4- resistance strain gages R1, R2, R3, R4.

After the necessary transformations, we get

U=E(R2R4-R1R3)[(R1+R2)(R3+R4)]-1.(4)

Determine the condition of the temporal stability of Nimes

U(t+Δt)=U(t),(5)

where U(τ+Δτ) - initial output signal at time (τ+Δτ);

U(τ) is the initial output signal at time τ.

After substituting in the expression (5) expressions (4) and ensure the necessary stability of the power source E(τ+Δτ)=E(τ), we obtain the condition for the stability of Nimes in expanded form

[R2(t+Δt)R4(t+Δt)-R1(t+Δt)R3(t+Δt)]××{[R1(t+Δt)+R2(t+Δt)]×[R3(t+Δt)+R4(t+Δt)]}-1==[R2(t)R4(t)-R1(t)R3(t)]×{[R1(t)+R2(t)]×[mrow> R3(t)+R4(t)]}-1(6)

Analysis of the obtained conditions shows that from the point of view of mathematics is needed for countless combinations of resistances of the strain gages and their functional dependencies on time. At the same time, any combination in the case of inequality of the different resistances of the strain gages bridge measuring circuit Nimes will require to meet the conditions of stability of various interrelated and accurate functional dependences of the resistances of the strain gauges from time to time.

In the analysis of the relationship of thin-film elements of the strain gauge (figure 1), we can determine the resistance of the j-th thin-film strain gauge at time τ and (τ+Δτ), respectively

Rj(t)=RPj(t)+2RPAj(t)+2RAj(t)+2R Kj(t)+2RKj(t)+2RKPj(t)+2RPj(t),(7)

Rj(t+Δt)=RPj(t+Δt)+2RPAj(t+Δt)+2RAj(t+Δt)+2RAKj(t+Δt)++2RKj(t+Δt)+2RKPj(t+Δt)+2RPj(t-Δt) ,(8)

where RPj, RAj, RKj, Rjaccordingly, the resistance of piezoresistive, adhesive, contact, conductive element of the j-th of the strain gauge; Rj, Rj, RKjaccordingly, the resistance of the transitions of the piezoresistive elements - adhesive, adhesive - contact, contact - conducting j-th of the strain gauge.

In the most General case, the resistance of each thin-film element of the strain gauge is completely determined by the specific surface resistance, the effective length and the effective width of the element or transition. Moreover, experimental studies of the long-term impact of external factors on the pressure sensors based on thin-film Nimes showed that the most significant parameters that determine the resistance of the strain gages, impact deformation, temperature and time. Therefore, in accordance with expressions (7), (8) to represent the resistance of the thin-film strain gages in the form of the following expressions:

Rj(t)=ρPJ(εPJ ,TPJ,t)lPJ(εPJ,TPJ,t)[bPJ(εPJ,TPJ,t)]-1++2ρPAJ(εPAJ,TPAJ,t)lPAJ(εPAJ,TPAJ,t)××[bPAJ(εPAJ,TPAJ,t)]-1+2ρAJ(εAJ,T AJ,t)lAJ(εAJ,TAJ,t)[bAJ(εAJ,TAJ,t)]-1++2ρAKJ(εAKJ,TAKJ,t)×lAKJ(εAKJ,TAKJ,t)[bAKJ(εAKJ,TAKJ,t)]-1+2ρKJ(εKJ,TKJ,t )lKJ(εKJ,TKJ,tKJ)[bKJ(εAKJ,TKJ,t)]-1++2ρKPJ(εKJ,TKJ,t)lKPJ(εKJ,TKJ,t)[bKPJ(εKJ,TKJ,t)]-1++2ρPJ(εPJ,TPJ,t)lPJ (εPJ,TPJ,t)×[bPJ(εPJ,TPJ,t)]-1,(9)

R(t+Δt)=ρPJ(εPJ,TPJ,t+Δt)lPJ(εPJ,TPJ,t+Δt)[bPJ(εPJ,TPJ,t+Δt)]-1++2ρPA J(εPAJ,TPAJ,t+Δt)×lPAJ(εPAJ,TPAJ,t+Δt)××[bPAJ(εPAJ,TPAJ,t+Δt)]-1+2ρAJ(εAJ,TAJ,t+Δt)lAJ(εAJ,TAJ,t+Δt)××[bAJ(εAJ,TAJ,t+Δτ/mi> )]-1++2ρAKJ(εAKJ,TAKJ,t+Δt)lAKJ(εAKJ,TAKJ,t+Δt)××[bAKJ(εAKJ,TAKJ,t+Δt)]-1++2ρKJ(εKJ,TKJ,t+Δt)lKJ(εKJ,TKJ,t+Δt)[bK J(εKJ,TKJ,t+Δt)]-1++2ρKPJ(εKJ,TKJ,t+Δt)××lKPJ(εKJ,TKJ,t+Δt)[bKPJ(εKJ,TKJ,t+Δt)]-1++2ρPJ(εPJ,TPJ,t+Δt)××lPJ(εPJ,TPJ,t )[bPJ(εPJ,TPJ,t)]-1(10)

where ρRJ, ρPAJ, ρAJ, ρAKJ, ρKJ, ρJ, ρKJeffective surface resistivity of the respective elements and transitions; lPJ, lPAJ, lAJ, lAKJ, lKJ, lJ, lJ- the effective length of the respective elements and transitions; bPJbPAJbAJbAKJbKJbKJbJeffective width of the respective elements and transitions of the j-th of the strain gauge; εRJ, εPAJ, εAJ, εAKJ, εKJ, εJ, εJ- relative deformation affecting the relevant elements and transitions; TRJ, TPAJTAJ, TAKJTKJ, TJ, TJtemperature affecting the relevant elements and transitions; indexPJ,AJ,KJ,Jindicates relevant characteristics or factors of the adhesive, the contact start elements j of the strain gauge; indexAJ ,AKJ,KJindicates relevant characteristics or factors of the resistive transitions - adhesive, adhesive - contact, contact - conducting j-of the strain gauge; j=1, 2, 3, 4 - the number in the strain gauge bridge circuit; τ - time reference point; Δτ - test time interval.

To ensure the independence of the resistances of the strain gauges from time to time it is necessary that the difference of the expressions (9) and (10) was equal to zero, that is,

ρPJ(εPJ,TPJ,t)lPJ(εPJ,TPJ,t)[bPJ(εPJ,TPJ,t)]-1++2ρPAJ(εPAJ,TPAJ,t) lPAJ(εPAJ,TPAJ,t)××[bPAJ(εPAJ,TPAJ,t)]-1++2ρAJ(εAJ,TAJ,t)lAJ(εAJ,TAJ,t)[bAJ(εAJ,TAJ,t)]-1++2ρAKJ(εAKJ,TAKJ,t )×lAKJ(εAKJ,TAKJ,t)[bAKJ(εAKJ,TAKJ,t)]-1+2ρKJ(εKJ,TKJ,t)lKJ(εKJ,TKJ,tKJ)[bKJ(εKJ,TKJ,t)]-1++2ρKPJ(εKJ,TKJ,t)l KPJ(εKJ,TKJ,t)[bKPJ(εKJ,TKJ,t)]-1++2ρPJ(εPJ,TPJ,t)lPJ(εPJ,TPJ,t)××[bPJ(εPJ,TPJ,t)]-1--ρPJ(εPJ,TPJ,t+Δt)lP J(εPJ,TPJ,t+Δt)[bPJ(εPJ,TPJ,t+Δt)]-1--2ρPAJ(εPAJ,TPAJ,t+Δt)×lPAJ(εPAJ,TPAJ,t+Δt)××[bPAJ(εPAJ,TPAJ,t+Δt)]-1--2ρAJ( εAJ,TAJ,t+Δt)lAJ(εAJ,TAJ,t+Δt)×[bAJ(εAJ,TAJ,t+Δt)]-1--2ρAKJ(εAKJ,TAKJ,t+Δt)lAKJ(εAKJ,TAKJ,t+Δt)××[bAKJ(εAKJ,TAKJ,t+Δt) ]-1--2ρKJ(εKJ,TKJ,t+Δt)lKJ(εKJ,TKJ,t+Δt)[bKJ(εKJ,TKJ,t+Δt)]-1--2ρKPJ(εKJ,TKJ,t+Δt)×lKPJ(εKJ,TKJ,t+Δt)[bKPJ(εKJ,TKJ ,t+Δt)]-1--2ρPJ(εPJ,TPJ,t+Δt)×lPJ(εPJ,TPJ,t)[bPJ(εPJ,TPJ,t+Δt)]-1=0,(11)

Due to the characteristic feature of the thin-film strain gauge changes its resistance when the temperature changes depends not only on temperature but also on the deformation States of the elements and transitions of the strain gauge. Then, in accordance with the expression (11) temperature coefficient of resistance may be the criterion of temporal stability of thin-film strain gauge. To determine the stability criterion It is MS refer to the expression (6), from which, taking into account the much smaller impact of temporary changes resistances of the strain gages on the amount of resistance compared with the impact on their difference, obtain the simplified condition time stability of Nimes

[R2(t+Δt)R4(t+Δt)-R1(t+Δt)R3(t+Δt)]=[R2(t)R4(t)-R1(t)R3(t)](12)

Given that in General the resistance change of the strain gauge ΔRjJRjΔT, where ΔTJthe temperature change of the j-th strain gauge testing, as well as equality of temperature changes of the strain gages in the test runs due to complete their perception of the test temperatures, the conditions (12) on equality edit the changes resistances of the strain gages, included in the opposite shoulders of the bridge circuit Nimes, provided when R2α2R4α4-R1α1R3α3. Multiplying the resulting expression for (R2α)-1to preserve the dimensionality °C-1get the claimed value.

Implementation of the proposed method in the production of thin-film strain sensors pressure provides improved temporal stability when exposed to factors not less than 1.7 times at a relatively low cost, which allows to increase the resource and service life of the sensors. Thus, the technical result of the invention is to increase the temporal stability, resource, service life by identifying at an early stage of manufacture potentially unstable Nimes, providing the pass for the further Assembly of the strain gauges with the same (within the selected criterion) a temporary change in resistance, including from the same speed degradation and relaxation processes in the strain gages included in the opposite shoulders of the bridge measuring circuit.

Sources of information

1. Belozerov E.M. pressure Sensor and method of its manufacture. Patent RU No. 2095772. Bull. No. 6. 10.11.97.

2. Belozerov E.M., Belozerova N.E. Method of manufacturing tonkel the night, a strain gauge pressure. RF patent №2423678. Bull. No. 19 of 10.07.11.

A method of manufacturing a pressure sensor based on thin-film nano - and microelectrical system (Nimes), which consists in polishing the surface of the membrane, forming therein a dielectric film and tensometric elements with low resistance vias and pads between them using the template testcustomermap layer having the configuration of a tensometric elements in areas shared with low resistance vias and pads, in the form of strips, including images of tensometric elements and their continuation in two opposite directions, and in areas shared with pads, overlapping configuration of the pads and remote from the strips plots, attaching lead wires to the contact pads in areas remote from the strips sections, wherein after attaching lead wires to the contact pads to seal tensometric elements with jumper wires and pads are subjected to exposure to full their perception test low and elevated temperatures, the values of which absolute values are respectively equal to not less than the maximum low and high temperatures during operation of the sensor, measure the resistance of the strain gages at work is their temperatures, determine the temperature coefficients of the resistances of the strain gages in the operating temperature range, calculate the criterion of temporal stability ratio
Ψthe=(R2α2R4α4-R1α1R3α3(R2α)-1,
where R1, R2, R3, R4- resistance respectively of the first, second, third and fourth strain gages Nimes in normal climatic conditions; α1α2α3α4- temperature coefficient of resistance, respectively, first, second, third, and fourth strain gages Nimes; R=0,25(R1+R2+R3+R4); α=0,25(α1234),
and if ΨtheταΔ,
where ΨταΔ- the maximum permissible value of time stability criterion, which is determined experimentally according to the statistics for a specific size of the sensor, then this Assembly write in technological waste.



 

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FIELD: physics.

SUBSTANCE: sensor has a housing (1) in which there is a nano- and micro-electromechanical system consisting of a membrane (2) which is integrated with the base (3). A heterogeneous structure (4) of thin films is formed on the membrane. Tensoresistors are formed in the structure (4) and lie on a circle on the periphery of the membrane. A cylindrical bushing (7) with a hole (8) is mounted on the base on the side of feeding the measured medium, symmetrically about the longitudinal axis of the sensor and said bushing lies inside the base with a gap from the membrane and the peripheral base in a region adjacent to the membrane. Elements of the first and the second measuring circuits, lying outside the housing, are placed in a common screen (9) made from material with high heat conductivity. Characteristics of structural components of the sensor are linked by a corresponding relationship.

EFFECT: reduced measurement error.

1 dwg

FIELD: physics.

SUBSTANCE: multifunctional module for measuring physical quantities includes a detecting element for measuring pressure which is a profiled area of a semiconductor silicon substrate on which a Wheatstone bridge is formed, a detecting element for measuring acceleration having a Wheatstone bridge, a detecting element for measuring temperature which is in form of a thermistor. The detecting elements for measuring pressure, acceleration and temperature have a single monolithic design on the semiconductor silicon substrate which is mounted between two glass insulators. The detecting element for measuring acceleration is in form of an inertia mass mounted on the semiconductor silicon substrate by a flexible suspension. The Wheatstone bridges of the detecting elements for measuring pressure and acceleration are based on polycrystalline silicon on a dielectric layer on the planar side of the semiconductor silicon substrate. On the glass insulators there are depressions on the side where the inertia mass of the detecting element for measuring acceleration is located for free displacement thereof.

EFFECT: wider natural frequency and range of measuring acceleration, wider temperature range and enabling simultaneous measurement of pressure, acceleration and temperature.

3 dwg

FIELD: blasting.

SUBSTANCE: method to manufacture a composite explosive for explosion welding, includes preparation and mixing of explosive components, at the same time prior to mixing the explosive component is recrystallised to produce a nanodisperse powder from an organic dissolvent in the form of compounds from the group of dimethyl formamide, dimethyl sulfide or acetone into water, the produced dispersion is stabilised under higher temperature of not more than 100°C with further evaporation of the organic dissolvent and drying of the residue, which is then mixed with an inert filler, and the composite explosive is formed. The substance produced by this method as an explosive component contains tetranitropentaerytrite, or octogene, or hexogene in the form of pre-transformed to ultradisperse condition with particle size of not more than 10-6-10-8 m in amount of 30-70 wt % and a powdery inert filler in the form of sodium bicarbonate - balance.

EFFECT: invention provides for the possibility to arrange a link through explosion of fine parts and thin-film elements of assembly structures, for instance, thin plates or foil, without deformation and damage due to provision of minimisation of explosive layer and reduction of critical detonation layer.

2 cl, 3 dwg, 1 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to production of polymers, specifically metal complex polymerisation catalysts, and can be used to produce trans-1,4-polyisoprene. Described is a method of obtaining a modified titanium-magnesium nanocatalyst for polymerisation of isoprenate by reacting magnesium with titanium tetrachloride and butyl chloride in volume ratio of 1/(63-190), followed by washing and further modification with phosphine of general formula R3P, where R=aryl, alkyl or a thiol of general formula R1SR2, where R1, R2=aryl, alkyl or carbon disulphide. In the nanocatalyst, the ratio phosphorus/titanium in the case of phosphine or sulphur/titanium in the case of thiol or carbon disulphide ranges from 1 to 20 mol/mol.

EFFECT: high stereospecificity of the catalyst with respect to isoprene and reduced amount of low molecular weight fractions in polyisoprene.

3 cl, 15 ex

FIELD: electrical engineering.

SUBSTANCE: all-fibre laser with ultrashort pulse length contains pump lasers connected in series, module of pump laser radiation input into ytterbium-doped fibre, splitter, polarisation controller, device for switching on in self-starting mode and mode synchronisation which is made as a saturated film absorber based on polymer composite with single-wall carbon nanotubes integrated into optical fibre. A part of the all-fibre laser containing ytterbium-doped fibre, module of pump laser radiation input into active fibre, isolating polariser and fibre splitter is made of monomode fibre with polarisation support. The saturated film absorber is located at surface of D-polished cladding of monomode fibre; at that plane of D-polished cladding of monomode fibre is set so that polarisation of transmitted radiation lies in this plane.

EFFECT: maintainability of stable polarisation at the output with generation of supershort pulses with wave length of 1 mcm.

1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of producing cyclohexane and derivatives thereof of general formula R=H, . The method involves producing saturated hydrocarbons and derivatives thereof, which can be used as semi-products in organic synthesis. The method involves hydrogenation of cyclohexene or a derivative thereof, which is selected from 1-(N-piperidino)cyclohexene-1,1-(N-morpholino)cyclohexene-1 or 1,4-dicyclohex-1-enylpiperazine with hydrogen gas at atmospheric pressure of hydrogen in the presence of a nanocatalyst in tetrahydrofuran medium at temperature of 50-70°C for 5-6 hours, followed by extraction of the end product. The nanocatalyst used is nickel nanoparticles which are obtained by reducing nickel (II) chloride with lithium aluminium hydride in situ. The method can also be used to obtain a wider range of cyclohexane derivatives which contain heterocyclic groups.

EFFECT: method enables to conduct the process at atmospheric pressure using a catalyst obtained using a simpler technique, which simplifies the method overall.

4 ex

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to chemical-pharmaceutical industry and veterinary science, and represents an immunomodulatory composition for animals which contains lactoferrin milk whey protein as active substance, and distilled water as a solvent. In addition to lactoferrin, the active substance contains lactalbumin and lactoglobulin milk whey proteins, wherein the active substance represents an aqueous solution of mixed milk whey proteins of the total protein concentration of 10 g/l, containing 10-20% of lactoferrin, 20-30% of lactalbumin, 60-70% of lactoglobulin; moreover, the active substance further comprises selenium nanoparticles in the following proportions, wt %: aqueous solution of mixed milk whey proteins of the total protein concentration of 10 g/l containing 10-20% of lactoferrin, 20-30% of lactalbumin, 60-70% of lactoglobulin, 0.1-100 selenium nanoparticles 00001-10, distilled water up to 100.

EFFECT: invention provides a higher immunostimulating effects on the cell and humoral immunity.

3 ex, 3 tbl

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to a powdered preparation for soft tissue regeneration with an antibacterial effect. The preparation contains 0.07-0.09 wt % of copper nanoparticles sized 30-40 nm, 0.03-0.05 wt % of zinc nanoparticles sized 30-70 nm, and low-molecular chitosan.

EFFECT: invention improves the effectiveness of wound healing, including in septic and infected ones, while simplifying the processes of preparing and using the preparation, and also prolonging a shelf life thereof.

2 cl, 3 ex

FIELD: physics.

SUBSTANCE: impregnable absorbent module based on a polymer composite with single-wall carbon nanotubes, made on single-mode optical fibre, having a core and cladding. The polymer composite contains a polymer which is mixed with single-wall carbon nanotubes, which is selected to absorb radiation with the required wavelength. A film of the composite with nanotubes is placed on a surface which is polished along one plane of the cladding of the fibre. According to the first version, the fibre is designed to transmit radiation in one direction; the impregnable absorbent module further contains a polariser which is made on a section of the single-mode fibre with cladding which is polished along said plane and lies before the polished section with the film made from the composite when radiation propagates in a given direction; the distance between the polariser and the absorbent enables deviation of the radiation polarisation vector by not more than 5 degrees. According to the second version, residual thickness of the fibre cladding ranges from 1 to 3 mcm; thickness of the film of the composite is not more than 1 mcm; said film is coated with an aluminium film with thickness of not more than 100 nm; the length of such a double-layer film ranges from 1 to 10 mm.

EFFECT: high optical stability of the absorbent.

4 cl, 3 dwg

FIELD: textiles, paper.

SUBSTANCE: cellulosic moulded product is proposed with a cellulosic matrix and dispersed therein inclusions of non-polar organic compound(s) which comprises at least one hydrophobic agent increasing viscosity and/or in which the inclusions are surrounded by plain and/or elongated hydrophobisated nanoparticles as the barrier material. A method is also proposed of production of such products by wet-dry extrusion process and their applications as paper or film.

EFFECT: proposed moulded products as compared to unmodified cellulosic fibers have significantly higher ability to accumulate heat or nonpolar active agents, and can be used in the textile industry.

27 cl, 2 dwg

FIELD: biotechnology.

SUBSTANCE: deoxyribonucleic acid (DNA) is separated from biological objects on carrier objects - gauze, paper, synthetic fabrics. The biological object - bone, horny tissue - is crushed. It is placed in a test tube containing a lytic buffer solution of the composition: 0.1 M Tris-HCl, 0.1 M EDTA, 0.1 M NaCl, 0.5% N-laurylsarcosil Na and proteinase K, pH 6-7. Cell lysate is obtained and is added with sorbent of magnetic nanoparticles of iron oxide Fe3O4, modified with chitosan. The mixture is stirred and incubated for 25-35 min. The test tube is placed on a magnetic rack and the mixture is divided into fractions - sorbent associated with DNA and the supernatant. The supernatant is removed. The residue is added with poured eluting buffer solution of the composition: 10 mM Tris-HCl, pH 7.4, 100 mM NaCl; 1 mM EDTA, and incubated. The test tubes are placed on a magnetic rack. The mixture is divided into fractions - sorbent - residue and supernatant - DNA, dissolved in the eluting buffer solution. The residue is removed. The final product of DNA is left in the supernatant.

EFFECT: invention enables to obtain DNA from different biological objects and increase the yield of the separated DNA not less than 1,5 times.

FIELD: oil and gas industry.

SUBSTANCE: invention refers to oil-processing and petrochemical industries. The invention refers to the method for processing of hydrocarbon-containing raw material, and namely heavy and/or residual raw material, in which to raw material there additionally added is metal organic salt having the following formula: M(OOC-R)n, or M(SOC-R)n or M(SSC-R)n, where R means alkyl, aryl, isoalkyl, tert-alkyl, alkylaryl, which possibly includes hydroxylic, keto-, amino-, carboxyl, thiocarbamic group, where n - 1-3, and M means transition metal from elements of the Periodic system, at decomposition of which there obtained are metal nanoparticles, or nanoparticles of those metals, based on 0.001-0.1 wt % of metal per mass of raw material; at that, as hydrocarbon additive, there used are paraffin hydrocarbons, or olefinic hydrocarbons, or fraction of shale tar, or their mixture in the quantity of 2.0-20.0 wt %.

EFFECT: increasing conversion degree of hydrocarbon-containing raw material; increasing the yield of distillate fractions.

3 cl, 22 tbl, 16 ex

Magnetic materials // 2244971

FIELD: magnetic materials whose axial symmetry is used for imparting magnetic properties to materials.

SUBSTANCE: memory element has nanomagnetic materials whose axial symmetry is chosen to obtain high residual magnetic induction and respective coercive force. This enlarges body of information stored on information media.

EFFECT: enhanced speed of nonvolatile memory integrated circuits for computers of low power requirement.

4 cl, 8 dwg

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