Electric sensor for hydrazine vapours |
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IPC classes for russian patent Electric sensor for hydrazine vapours (RU 2522735):
     
 Method for obtaining gas-sensitive material based on zinc oxide to acetone vapours / 2509302
According to the invention, a method for obtaining material based on zinc oxide, which is sensitive to acetone vapours, consists in preparation of sol by dilution of non-organic zinc salt in alcohol, in addition of tetraethoxy silane, distribution of sol along a substrate surface, annealing and processing of the obtained material by action on it of a flow of electrons accelerated up to energy of 540-900 keV at absorbed dose of 25-200 kGy.
 Method of measurement for gaseous media polycomposition / 2504760
Method as per the invention implies usage of sensors with their number corresponding to the number of unknown components to be measured. Each of the components to be measured is natural input value for one sensor, i.e. the sensor for this component is the most selective (sensitive) one and the other sensors are less sensitive to this component. Nevertheless each sensor is graduated for each component separately in order to measure gaseous medium polycomposition.
 Electrochemical sensor and method of making said sensor / 2502992
Invention discloses a method of making an electrochemical sensor with a detector area, electrical conductivity (σ) of which is set via tunnelling, ionisation or hopping processes, and in which electrochemical interaction with a defined substance is established; wherein the detector area is made by local application of energy, preferably by electron beam-induced deposition, wherein gaseous precursor substances present in the deposition area in immediate proximity to the substrate are energy-activated for conversion, wherein the conversion products are deposited in solid and nonvolatile form on the substrate. Also disclosed is an electrochemical sensor made using the described method.
 Method to determine residual water saturation and other forms of combined water in core material / 2502991
In the method to determine water saturation of core and other forms of combined water in the core material includes preparation of a sample from core, extraction and drying of the sample, modelling of bed conditions in the core sample, filtration of mineralised water via the core sample and serial measurement of intermediate values of current passing through the sample as AC voltage is applied to it in process of filtration, building of dependence of the electric signal value on the water saturation of the core sample. Additionally, in accordance with the invention, prior to measurements the core is insulated with a thin dielectric shell and placed between electrodes of the capacitance measurement cell, and current values passing via the sample at different values of water saturation (from 0 to 100%), is determined by the method of contactless high-frequency conductivity measurement, for instance, by the method of non-linear unbalanced bridge, supplied with the high-frequency voltage with frequency of 2-10 MHz, using the produced dependence of values of the electric signal on water saturation of the core sample, three areas are identified with different values of rate of rise with growth of water saturation, and borders of energetically different categories of combined water in the core, including the residual water saturation, are determined as points of bending between specified areas with different values of signal slope.
 Gas metering device and method of its operation / 2502066
Device comprises: a sensor comprising a sensitive element and a heating element configured for heating of the sensitive element to the previously set operating temperature, besides, the sensitive element is perceptive to the specified gas so that at least one electric property of the sensitive element varies depending on presence of the specified gas, besides, the electric property of the sensitive element is measured by a gas metering device; and a control circuit comprising a heating element controller connected to the heating element and measuring its electric property, besides, the control circuit has a source of heating energy supplying energy to heating element. The controller of the heating element is connected with a source of heating energy and controls its operation depending on measurement of the electric property of the heating element; a facility of pulse modulation connected with the controller of the heating element, the source of heating energy for control of the energy value supplied to the heating element. At the same time the facility of pulse modulation is made as capable of generation of the first set of energy pulses, having certain duration, and the second set of energy pulses, having another, shorter duration for maintenance of temperature of the heating element substantially at the permanent level. Also the invention relates to the method for manufacturing and method of operation of the gas metering device.
 Method of analysis of gas mixture composition and gas analyser for its realisation / 2502065
Analysed gas mixtures are sent via a gas analyser with sensors installed in it, electric signals are measured with the help of sensors, using calibrating functions produced on gas mixtures of available composition, values of concentrations of individual gas mixture components read by every sensor are determined, additional measurement of electric signals from sensors is carried out, during realisation of which chemical filters are installed at inlets of sensors, and the filters separate from a gas mixture arriving to each sensor the individual component of the gas mixture determined by this sensor, gas mixtures without individual components are sent via sensors, electric signals are measured with the help of sensors, which correspond to gas mixtures in absence of these individual components, and then the difference is determined between electric signals produced from sensors in presence of individual components of the gas mixture determined by each sensor, and in their absence, and with usage of calibration functions produced on gas mixtures of available composition, by values of these differences of electric signals they determine actual values of concentrations of individual components of the gas mixture, determined by each sensor. Also a gas analyser is proposed for realisation of the above method.
 Gas metering device and method of its manufacturing / 2488106
Invention relates to a gas metering device for measurement of availability of a sought-for gas in a fluid medium, comprising a body of a sensor, which defines the sensor's cavity stretching from an open end of the sensor body, at the same time the specified open end is closed with a screening element, besides, the fluid medium flows into the sensor cavity via the open end; and a sensor installed inside the sensor cavity to sense availability of the sought-for gas, a heating element, which has electrodes, arranged on one side of the substrate between the specified sensor and the specified open end in the sensor's cavity, with a sensor located on the other side of the substrate, by means of which the heating element heats the sensor via the substrate, at the same time the sensor has a sensitive element on the specified side of the sensor further from the hole, at the same time the sensitive element is arranged inside the sensor cavity so that the sensitive element is faced away from the hole. The invention also relates to the method of gas metering device manufacturing for measurement of availability of the sought-for gas in the fluid medium.
 Ammonia sensor / 2478942
Sensor according to the invention has a non-conducting substrate made from graphite fluoride, which is obtained by fluorinating graphite, on which there a sensitive layer. The sensitive layer is formed by treating the graphite fluoride surface with vapour of a reducing agent. The reducing agent used is hydrazine-hydrate, hydrazine, water or hydrogen peroxide, for example. Operating characteristics of the sensor are restored by blowing with air.
 Gas sensor / 2469301
Semiconductor base is made from a polycrystalline film of copper iodide and the substrate is the electrode pad of a piezo-quartz resonator.
 Semiconductor gas analyser / 2469300
Semiconductor base is made from a polycrystalline film cadmium selenide doped with indium antimonide. The substrate is the electrode pad of a piezo-quartz resonator.
 Diagnostics of flaws on metal surfaces / 2522709
Gold cylindrical nanoparticles not over 100 nm in length are sprayed onto surface of tested object, depth of the ply of said particles allowing the filling of cavities of would-be fractures. Then, said surface is dried to remove sprayed ply therefrom. Then, object surface is subjected to non-interlaced scan by fs-laser beam. At a time, intensity of two-photon luminescence signal is registered in every area under analysis to fix the location of said area corresponding to object coordinate. 2D array of two-photon luminescence signal intensities is formed to produce the map of distribution of nanoparticle luminescence intensities excited by laser radiation.
 Microwave plasma converter / 2522636
Invention may be used when producing carbon nanotubes and hydrogen. Microwave plasma converter comprises flow reactor 1 of radiotransparent heat-resistant material, filled with gas permeable electrically conductive material - catalyst 2 placed into the ultrahigh frequency waveguide 3 connected to the microwave electromagnetic radiation source 5, provided with microwave electromagnetic field concentrator, designed in the form of waveguide-coax junction (WCJ) 8 with hollow outer and inner conductors 9, forming discharge chamber 11 and secondary discharge system. Auxiliary discharge system is designed from N discharge devices 12, where N is greater than 1, arranged in a cross-sectional plane of discharge chamber 11 uniformly in circumferential direction. Longitudinal axes of discharge devices 12 are oriented tangentially with respect to the side surface of discharge chamber 11 in one direction. Nozzle 10 is made at outlet end of inner hollow conductor 9 of WCJ 8 coaxial. Each of discharge devices 12 is provided with individual gas pipeline 13 to supply plasma-supporting gas to discharge zone.
 Method of determining angle of misorientation of diamond crystallites in diamond composite / 2522596
Invention can be used in the field of elaboration of diamond-based materials for magnetic therapy, quantum optics and medicine. A method of determining an angle of misorientation of diamond crystallites in a diamond composite includes placement of the diamond composite into a resonator of an electronic paramagnetic resonance (EPR) spectrometer, measurement of EPR spectrums of nitrogen-vacancy NV-defect in the diamond composite with different orientations of the diamond composite relative to the external magnetic field, comparison of the obtained dependences of EPR lines with the calculated positions of EPR lines of NV-defect in the diamond monocrystal in the magnetic field, determined by the calculation. After that, the angle of misorientation of the diamond crystallites is determined by an increase of width of EPR line in the diamond composite in comparison with the width of EPR line in the diamond monocrystal.
 Method of modifying envelopes of polyelectrolyte capsules with magnetite nanoparticles / 2522204
Invention relates to a method of modifying envelopes of polyelectrolyte capsules with magnetite nanoparticles. The disclosed method involves producing a container matrix in form of porous calcium carbonate microparticles, forming envelopes of polyelectrolyte capsules by successive adsorption of polyallyl amine and polystyrene sulphonate and modifying with magnetite nanoparticles on the surface of the container matrix or after dissolving the matrix through synthesis of magnetite nanoparticles via chemical condensation.
 Method of producing nanostructured metal oxide coatings / 2521643
Method comprises preparing an alcohol solution of β-diketonates of one or more p-, d- or f-metals with concentration 0.001h2 mol/l; heating the solution to 368-523 K and holding at said temperature for 10-360 minutes to form a metal alkoxo-β-diketonate solution; depositing the obtained solution in droplets at the centre of a substrate being rotated at a rate of 100-16000 rpm, or immersing the substrate into said solution at a rate of 0.1-1000 mm/min at an angle of 0-60° to the vertical; holding the substrate with a film of the alkoxo-β-diketonate solution at 77-523 K until mass loss ceases, to form xerogel on the surface of the substrate; crystallising oxide from the xerogel at 573-1773 K.
 Method for preparing nanodiamonds with methane pyrolysis in electric field / 2521581
Invention may be used in medicine in producing preparations for a postoperative supporting therapy. What is involved is the high-temperature decomposition of methane on silicone or nickel substrate under pressure of 10-30 tor and a temperature of 1050-1150°C. The heating is conducted by passing the electric current through a carbon foil, cloth, felt or a structural graphite plate whereon the substrates are arranged. An analogous plate whereon a displacement potential from an external source is sent is placed above the specified plate. Nanodiamonds of 4 nm to 10 nm in size are deposited on the substrates.
 Agent with anti-stroke action, and method for preparing it / 2521404
Invention concerns an agent having an anti-stroke action and representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size, and a method for preparing it.
Polymer nanocomposite with controlled anisotropy of carbon nanotubes and method of obtaining thereof / 2520435
Invention relates to the field of polymer materials science and can be used in aviation, aerospace, motor transport and electronic industries. Nanotubes are obtained by a method of pyrolytic gas-phase precipitation in a magnetic field from carbon-containing gases with application of metals-catalysts in the form of a nanodisperse ferromagnetic powder, with the nanotubes being attached with their butt ends to ferromagnetic nanoparticles of metals-catalysts. Magnetic separation of the powder particles with grown on them nanotubes, used in obtaining a polymer-based composite material, is carried out. After filling with a polymer, a constant magnetic field is applied until solidification of the polymer takes place. The material contains carbon nanofibres and/or a gas-absorbing sorbent, for instance, silica gel, and/or siliporite, and/or polysorb as a filling agent.
 Test object for calibrating microscopes in micrometer and nanometer ranges / 2519826
Test object for calibrating microscopes is in form of groove structures whose walls have an inclined profile, a flat base and a different width on the surface and at the bottom. A constant angle between the side wall and the bottom plane is maintained for all elements. Linear dimensions of at least part of the elements differ from each other by a certain number of times, and linear dimensions of the largest element can be measured with high accuracy on calibrated measuring equipment used when taking measurements.
 Antipsychotic agent and method for preparing it / 2519761
Invention concerns an antipsychotic agent representing the amino acid glycine immobilised on the detonation-synthesised nanodiamond particles of 2-10 nm in size, and a method for preparing it.
 Nanoliposome with application of etherificated lecitin and method of obtaining such, as well as composition for prevention or treatment of skin diseases including such liposomes / 2418575
Invention relates to medicine and deals with nanoliposome which includes liposomal membrane, contains ethgerificated lecitin and one or more physiologically active ingredients, incorporated in the internal space of liposomal membrane, method of obtaining such, as well as composition for prevention or treatment of skin diseases, containing nanoliposome.
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FIELD: chemistry. SUBSTANCE: electric sensor for hydrazine vapours contains a dielectric substrate, on which placed are: electrodes and a sensitive layer, which changes photoconductivity as a result of hydrazine vapour adsorption; the sensitive layer consists of the following structure - graphene-semiconductor quantum dots, whose photoconductivity decreases when hydrazine molecules are adsorbed on the surface of quantum dots proportionally to the concentration of hydrazine vapour in a sample. If hydrazine vapours are present in the air sample, hydrazine molecules are adsorbed on the surface of quantum dots, decreasing intensity of quantum dot luminescence, which results in decrease of graphene conductivity proportionally to the concentration of hydrazine vapours in the analysed sample. EFFECT: increase of sensitivity, decrease of determination sluggishness and simplification of the sensor manufacturing. 1 ex, 7 dwg
The invention relates to the field of analytical instrumentation, namely, devices and materials for detecting and determining the concentration of vapors of hydrazine in the atmosphere or an air sample (chemical sensors), and can be used in medicine, biology, ecology and various industries. Known colorimetric sensor on a pair of hydrazine "Method and device for determination of hydrazine and hydrazine derivatives (U.S. Patent number US 4,789,638, the application 07/046,385, publication date 06.12.1988, the priority date of 06.05.1987) [1], the principle of detection of hydrazine which is based on the change of the absorption parameters colorimetric indicator in the presence of iodine, which in turn is released during the interaction of Iodate or iodite with pairs of hydrazine. Common deficiencies colorimetric sensors include low sensitivity (0.02 mg/m3=0,02 million-1when the maximum allowable concentration of hydrazine 10 billion-1), the impossibility of quantitative remote sensing estimate the concentration of hydrazine in pairs, short service life caused by the consumption of reagents sensitive layer. Known fluorescent sensor on a pair of hydrazine "Fluorescent detection of hydrazine, monomethylhydrazine, and 1,1-dimethylhydrazine by derivatization with aromatic dicarboxaldehyde" (Patent of the SHA No. US 5,719,061, application 08/326,518, date of publication, 17.12.1998, the priority date of 20.10.1994) [2]. The principle of detection of hydrazine in fluorescent sensor based on detection of changes in the spectral-luminescent characteristics (in this case, by changing the position of the band maximum luminescence) reagent sensitive layer in contact with vapors of hydrazine as a result of chemical interaction of the reagent with pairs of hydrazine. Compared with colorimetric sensors luminescence sensors have higher sensitivity (0,004-2,000 million-1and help to quantify the concentration of hydrazine in pairs. Common deficiencies of this type of sensors can be attributed to the short lifespan associated with the consumption of reagents and photobleaching sensitive layer. Known electrochemical sensor on a pair of hydrazine "Amperometric sensor and method for the detection of gaseous analytes containing working electrodes made of pyrolytic graphite" (US Patent # US 2010/0147705, the application 11/722,333, published 17.07.2010, the priority date of 22.12.2005) [3]. The principle of operation of electrochemical sensors based on the phenomenon of flow-specific chemical reactions (electrochemical reaction) in the electrochemical cell that represents the container of electrolyte solution with electrodes (anode and cathode). Analyte enters into chemical reacts the Yu with electrolyte, fill the cell. As a result, the solution arise charged ions between the electrodes begins to flow electric current, proportional to the concentration of the analyzed component in the sample. The disadvantages of electrochemical sensors are high inertia (the average response time of 2-3 min), the sensitivity of the signal level to the ambient conditions (temperature and humidity) and the inability of the remote signal. Closest to the claimed invention and taken as a prototype Sensor vapor concentration of hydrazine (Patent RF №2034284, IPC G01N 27/12, publication date 30.04.1995, the priority date of 07.08.1992) [4], containing sensitive layer changing in the interaction with hydrazine their electrophysical characteristics. The sensor includes a dielectric substrate on which the electrodes and a sensitive layer consisting of a porous sorbent (e.g., silica)containing heteropolysaccharide row 12. Detection of vapors of hydrazine occurs due to the reaction of the complexing molecules of hydrazine with cationic part of heteropolysaccharide (HCC), which is the result of stabilization of the higher valence state of cobalt atoms or manganese enters into an intramolecular redox reaction, leading to a sharp changed the Yu electrophysical properties HCC. The prototype has the following disadvantages: 1. The insufficient sensitivity of the sensor: 0.5 to 1.0 million-1. 2. Long response time: 15-30 seconds. 3. Quite complex for technology-intensive manufacturing process sensitive layer of the sensor associated with the complexity of the synthesis of heteropolysaccharide used as a sensitive connection to a pair of hydrazine. The task of increasing the sensitivity and reducing the inertia response while simplifying the manufacturing technology of the sensor. The essence of the invention lies in the fact that the electrical sensor on a pair of hydrazine contains a dielectric substrate on which the electrodes and the sensing layer, changing the photoconductivity as a result of adsorption of vapors of hydrazine, with the sensitive layer consists of a structure of graphene-semiconductor quantum dots, photoconductivity which decreases as the adsorption of molecules of hydrazine on the surface of quantum dots is proportional to the concentration of vapors of hydrazine in the sample. The decrease in the photoconductivity of the hybrid structure of Gr-CT is proportional to the concentration of vapors of hydrazine in the analyzed sample is due to the following. In the absence of vapors of hydrazine in the hybrid structure is sensitized with quantum dots photoconductivity of graphene, due to the military phototransfer holes from CT to graphene [G. Konstantatos, M. Badioli, L. Gaudreau, J. Osmond, M. Bemechea, F. Pelayo, G. de Arquer, F. Gatti & Frank H. L. Koppens. Hybrid graphene-quantum dot phototransistors with ultrahigh gain// Nature Nanotechnology, 7, 363-368 (2012)] [5]. It should be noted that the speed of the phototransfer holes in this system is limited by the lifetime of the excited state of the quantum dots (tens of nanoseconds). The presence of vapors of hydrazine in the analyzed test results to reduce the decay time of the luminescence CT (reducing the lifetime of the excited state CT) due to the adsorption of molecules of hydrazine on the surface of quantum dots and, as consequence, to decrease the effectiveness of phototransfer holes from CT to graphene and reduction sensitization of the photoconductivity of graphene. The proposed sensor for detecting vapors of hydrazine has the following advantages: 1. Higher sensitivity and accuracy of determining the concentration of vapors of hydrazine. This advantage is due to the greater mobility of charge carriers in graphene sheets in comparison with heteropolysaccharide used in the prototype as a sensitive layer. 2. A lower response time. This advantage is provided by the high rate constants of the processes of electron transfer, the underlying photophysical changes in the conductivity of the hybrid structure of graphene-quantum dot. 3. The simplification of the manufacture of the population of the sensor. This advantage is realized due to the fact that when creating a sensor element sensitive to pairs of hydrazine, does not require complex and expensive technologies of synthesis of specific chemical compounds, and to create a sensitive layer of the sensor it is only necessary to put a layer of semiconductor quantum dots on the surface of graphene sheets. The essence of the invention is illustrated in figure 1-7 are: Figure 1. A schematic depiction of a hybrid structure of graphene-semiconductor quantum dots (G-CT). Figure 2. Absorption spectra and luminescence of the solution structures of graphene-quantum dots: 1 - structure of graphene-quantum dot; 2 - graphene; 3 - quantum dot. The inset shows the luminescence spectrum of the solution structures, the wavelength of the exciting light is 405 nm. Figure 3. The Raman spectrum of the hybrid structure of graphene-quantum dot. The inset in a larger scale shows the area with strips of CdSe quantum dots (lane 204 cm-1) and graphene (strip 1100, 1350 and 1580 cm-1). Figure 4. Images and spectra of luminescence structures of graphene-quantum dot on the surface of glass slides obtained using fluorescent LSM710 confocal microscope (Zeiss, Germany), the excitation semiconductor laser with a wavelength of 405 nm, the size of the ska is investing 50×50 μm 2: a - micro fluorescent and channel bandwidth (arrows show the structure of the graphene-quantum dots); b - luminescence spectra of the respective structures. Figure 5. Electric circuit for recording the current flowing through the sensing element: 4 - sensitive layer, 5 - metal electrodes, 6 - substrate SiO2. 6. Schematic representation of the setup for controlled feeding/pumping vapors of hydrazine: 7 - sensor element; 8 - the camera that is populated with pairs of hydrazine; 9 - camera with hydrazine hydrate; 10 is sealed tube; 11 - aqueous solution of hydrazine; 12 valve; 13 - bend to remove vapors of hydrazine from the chamber 8; 14 - gate. 7. The dependence of the photocurrent Ifa hybrid structure of graphene-quantum dot from the vapor concentration of hydrazine in the analyzed sample; It- dark current flowing through the sensing layer in the absence of photo radiation quantum dots. Example. To demonstrate the possibility of creating hybrid structures of graphene-quantum dot solution brightly luminescent hydrophobic colloidal semiconductor quantum dots CdSe/ZnS with a core diameter of 5 nm in hexane, synthesized according to the procedure of high-temperature ORGANOMETALLIC synthesis described in (V.O. Dabbousi, J. Rodriguez-Viejo, F.V. Mikulec, J. R. Heine, H. Mattoussi, R. Ober, K.F. Jensen, and M.G. Bawendi: (CdSe)ZnS Core-Shell Quantum Dts: Synthesis and Characterization of a Size Series of Highly Luminescent Nanocrystallites// J. Phys. Chem. B, 1997, 101 (46), pp.9463-9475) [6], was mixed with graphene plates, obtained from natural high-oriented graphite according to the procedure described in [F.P. Rouxinol, R.V. Gelamo, R.G. Amici, A.R. Vaz, St. A. Moshkalev: Low contact resistivity and strain in the suspended multilayer graphene Appl. Phys. Lett. 97, 253104 (2010)] [7]. Schematic representation of gibridnoi structure of graphene-quantum dot is shown in figure 1. Figure 2 shows absorption spectra and luminescence of the mixture G-CT in hexane, for comparison, also shows the absorption spectra of graphene and CT (Figure 2, curves 2 and 3, respectively ). In the absorption spectrum of the solution structures (Figure 2, curve 1) see the contribution of the absorption bands of graphene (D. Li, M.V. Muller, Sc. Gilje, R.B. Kaner & G.G. Wallace Processable aqueous dispersions of graphene nanosheets Nature Nanotechnology 3, 101-105 (2008)) [8] with a maximum in the region of 270 nm and the CT absorption band (band with maximum at 610 nm). There luminescence of quantum dots, indicating the absence of the quenching of the luminescence of quantum dots adsorbed on the surface of graphene sheets. 3 shows the Raman spectra of the hybrid structure of GR-CT on a glass slide. In the spectrum of the broad band luminescence CT with maximum 3055 cm-1there are characteristic bands, which indicate the presence in the sample of graphene plates (strips 1100, 1350 and 1580 cm-1) semiconductor and the quantum dots CdSe/ZnS (lane 204 cm -1). 4 shows images of hybrid structures Gr-CT on the surface of glass slides obtained using a confocal microscope. It is seen that the graphene sheets decorated with quantum dots, the luminescence spectrum which corresponds to the range of luminescence data of quantum dots in solution. To create the sensor element is a layer of semiconductor quantum dots deposited on the surface of graphene plates, applied by spin-coating on a dielectric substrate with metal electrodes formed on her lithographically. Then the sensor element connected to the electrical circuit in accordance with Figure 5. To study the influence of the vapor of hydrazine on the photoconductivity of hybrid structures G-CT, the sensor element was placed in a sealed chamber, to which was provided controlled release of air containing vapors of hydrazine. Figure 6 shows a schematic depiction of a camera for the controlled feeding/pumping vapors of hydrazine. The sensor element 7 is placed in an airtight chamber 8, which is connected with the chamber 9. In the chamber 9 through the opening closed by a stopper 10 is placed aqueous solution of hydrazine 11. After establishing in the chamber 9 of the equilibrium vapor concentration of hydrazine valve 12 is opened and the chamber 8 is filled with pairs of hydrazine specific to the centration. The sensor element 7 is maintained in the vapor of hydrazine fixed time (for example, within 1 minute). Then the sample is removed and registration of the current flowing through the sensor element. Figure 7 shows the dependence of the photocurrent flowing through the sensor element, the vapor concentration of hydrazine in the sample. It is seen that the magnitude of the photocurrent Ifsignificantly higher than the dark current Itflowing through the sample in the absence of photo radiation sensor element, and its value decreases proportional to the concentration of vapors of hydrazine in the analyzed sample. For reuse gibridnykh structures Gr-CT as a sensor element is necessary after the interaction of the sample with pairs of hydrazine to carry out its desorption from the surface of quantum dots. For this we used the setup shown in Fig.6. The sensor element 7, reacted with pairs of hydrazine were placed in the chamber 8, to the tube 13 with the valve 14 was connected to a vacuum pump. The pumping of air leads to a decrease in air pressure in the chamber 8 and, consequently, desorption of the molecules of hydrazine from the surface of quantum dots. It should be noted that while there was an increase of photoconductivity hybrid structure of Gr-CT to the initial level. Thus, solved the problem of the increase of h is stateliest, reduce inertia determine the concentration of vapors of hydrazine, increasing durability and ease of manufacture of the sensor. Sources of information 1. US patent # US 4,789,638, the application 07/046,385, publication date 06.12.1988, the priority date of 06.05.1987. 2. US patent # US 5,719,061, the application 08/326,518, date of publication, 17.12.1998, the priority date of 20.10.1994. 3. US patent # US 2010/0147705, the application 11/722,333, published 17.07.2010, the priority date of 22.12.2005. 4. The patent of Russian Federation №2034284, the application 5058002/25, publication date 30.04.1995, the priority date of 07.08.1992. 5. V.O. Dabbousi, J. Rodriguez-Viejo, F.V. Mikulec, J. R. Heine, H. Mattoussi, R. Ober, K. F. Jensen, and M.G. Bawendi: (CdSe)ZnS Core-Shell Quantum Dots: Synthesis and Characterization of a Size Series of Highly Luminescent Nanocrystallites//J. Phys. Chem. B, 1997, 101 (46), pp.9463-9475. 6. G. Konstantatos, M. Badioli, L. Gaudreau, J. Osmond, M. Bemechea, F. Pelayo, G. de Arquer, F. Gatti & Frank H.L. Koppens. Hybrid graphene-quantum dot phototransistors with ultrahigh gain// Nature Nanotechnology, 7, 363-368(2012). 7. F.P. Rouxinol, R.V. Gelamo, R.G. Amici, A.R. Vaz, St. A. Moshkalev: Low contact resistivity and strain in the suspended multilayer graphene Appl. Phys. Lett. 97, 253104 (2010). 8. D. Li, M.V. Muller, Sc. Gilje, R.B. Kaner & G.G. Wallace Processable aqueous dispersions of graphene nanosheets Nature Nanotechnology 3, 101-105 (2008). Electric sensor on a pair of hydrazine containing dielectric substrate on which the electrodes and the sensing layer, changing the photoconductivity as a result of adsorption of vapors of hydrazine, characterized in that the sensitive layer consists of a structure of graphene-semiconductor the suspension point, photoconductivity which decreases as the adsorption of molecules of hydrazine on the surface of quantum dots is proportional to the concentration of vapors of hydrazine in the sample.
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