Thermoregulation system for biosensors based on field-effect transistors with a nanowire channel
Thermoregulation system for biosensors based on field-effect transistors with a nanowire channel
G. V. Nibudin$^1$, I. I. Tsiniaikin$^1$, G. V. Presnova$^2$, M. Yu. Rubtsova$^2$, A. A. Popov$^1$, P. O. Mikhailov$^1$, A. S. Trifonov$^1$, O. V. Snigirev$^1$, V. A. Krupenin$^1$, D. E. Presnov$^{1,3}$
In this work we present an automatic thermoregulation system for biosensors based on field-effect transistors with a nanowire channel, which provides full control on the required temperature regime in bioanalytical analises. The system elements, including field-effect transistors with a nanowire channel, temperature sensors and heaters, were fabricated on a single silicon cristal using electron beam lithography, reactive ion etching and high-vacuum deposition techniques. Unicue electronics have been developed to control and maintain temperature. The dependence of thermometer readout on heating power was measured, which is in good agreement with the results of numerical simulation. A demonstration of a thermoregulation system with PID-feedback was carried out, ensuring the establishment of a desiered temperature in the range of 30-70 degrees in 18 seconds in liquid. A demonstration of a thermoregulation system for detecting nucleic acids was carried out using synthetic single-stranded DNA, which is a gene fragment from the bacterium Escherichia coli. The minimal detectable response was observed for a sample with a concentration of 3 fM.
Show AbstractCreation of the indirect-drive cryogenic target with the solid deuterium layer
Creation of the indirect-drive cryogenic target with the solid deuterium layer
E. Yu. Zarubina$^{1,2}$, M. A. Rogozhina$^1$, I. A. Ghugrov$^1$
An indirect-drive cryogenic target is necessary for research in the field of laser thermonuclear fusion at a megajoule energy level facility. Solid fuel layer in the target must meet high requirements: a roughness of the inner cryolayer surface must be less than 1 µm, deviations from the sphericity and the concentricity must be less than 1%. This paper describes the results of the research on meeting these requirements, notably, cryolayer formation and its characterization. Due to the slow crystallization method of the deuterium layer with its simultaneous heating by IR radiation it is possible to obtain deviations from the sphericity and the concentricity of the inner cryolayer surface within limits of 2%, the roughness - within limits of 20 mkm. Theoretical thermal calculations of the target construction are compared with experiment. The program system was developed using the optical shadow method which makes it possible to measure liquid fuel when filling the shell during the performance of the experiment, to perform the characterization of the solid cryogenic layer parameters, to evaluate characterization results robustness.
Show AbstractPlasmon energy losses of electrons in multilayer dielectric structures
Plasmon energy losses of electrons in multilayer dielectric structures
A. N. Vasil'ev
The possibilities of engineering energy losses of electrons created in the cascade process of electron-electron scattering during the interaction of multilayer dielectric structures with ionizing radiation are considered. It is shown that the contribution of surface plasmons associated with layer boundaries to electron energy losses is significant only for nanometer layer thicknesses and increases with increasing electron energy. At the same time, surface states associated with longitudinal optical phonons in ionic crystals significantly change energy losses during electron thermalization and can lead to an increase in the efficiency and growth rate of scintillation in nanostructured systems.
Show AbstractOn activation studies of photonuclear reactions on gamma-beams from backward Compton scattering at Egamma < 40 MeV
On activation studies of photonuclear reactions on gamma-beams from backward Compton scattering at Egamma < 40 MeV
S. S. Belyshev$^1$, V. V. Varlamov$^2$, L. Z. Dzhilavyan$^3$, A. A. Kuznetsov$^{1,2}$, A. M. Lapik$^3$, A. L. Polonski$^3$, A. V. Rusakov$^3$, V. I. Shvedunov$^2$
For the program of studying photonuclear reactions on gamma-beams of the source from backward Compton scattering under developing, when the output energy is Egamma < 40 MeV, activation experiments are proposed as initial ones, which are important both for developing methods for tuning and monitoring gamma-beams, and for studying the excitation of pygmy and giant resonances in atomic nuclei and the multiplicity of photoneutrons from the processes of deexcitation of giant resonances.
Show AbstractTaking into account the distribution of the noise level along the wavelength during broadband control of the deposition process of optical coatings
Taking into account the distribution of the noise level along the wavelength during broadband control of the deposition process of optical coatings
A. N. Sharov, S. A. Sharapova$^2$, A. V. Tikhonravov$^2$, A. G. Yagola$^3$
The paper presents numerical results of simulations of the deposition process of a complex optical coating using broadband monitoring of this process in the case when the noise level in the measured transmittance coefficient has an uneven distribution along the wavelength. The influence on the accuracy of data control at the edges of the measured wavelength range, where the error in the transmittance coefficient is maximum, is investigated. It is shown that when a part of the data is removed at the edges of the range, the self-compensation coefficient of the deposition process errors almost does not change, while the average norm of the error vector of layer thicknesses significantly decreases. Thus, it is shown for the first time that taking into account the effect of self-compensation of errors in broadband control opens up the possibility of a reasonable choice of the optimal spectral range of optical control for practice.
Show AbstractStresses in silicon dioxide films deposited from dielectric targets: results of atomistic modeling
Stresses in silicon dioxide films deposited from dielectric targets: results of atomistic modeling
F. V. Grigoriev, V. B. Sulimov, A. V. Tikhonravov
The previously proposed method of molecular dynamics simulation of the deposition of thin films from metal targets is adapted to the case of dielectric targets and applied to silicon dioxide films. The possibility of not only silicon atoms leaving the target, but also clusters with oxygen atoms was taken into account by adding O=Si=O molecules to the flow of deposited atoms. Atomistic film clusters were obtained by high-energy and low-energy deposition at different percentages of molecules in the flow of deposited atoms. The values of the stress tensor components are calculated. With high-energy deposition, compressive stresses are observed, with low-energy deposition, tensile stresses are observed. The absolute values of the diagonal components of the stress tensor increase with increasing proportion of molecules in the flow of deposited atoms.
Show AbstractMultibit failures of the spacecraft's onboard electronics from a single particle of cosmic radiation
Multibit failures of the spacecraft's onboard electronics from a single particle of cosmic radiation
N. G. Chechenin, N. V. Novikov, A. A. Shirokova
The analysis of the effect of high-energy protons of space radiation on the onboard electronics of the spacecraft is carried out. It is shown that protons can cause nuclear reactions with atomic nuclei of electronics material. The residual nuclei formed as a result of a nuclear reaction have sufficiently high energy to cross the sensitive areas of several bits of electronics, and the high ionizing ability of nuclear fragments allows generating an excess charge of carriers exceeding the critical charge for the failure to occur simultaneously in several bits of the electronic device
Show AbstractPlasma dynamics of a two-frequency capacitive discharge in an Ar/Xe mixture
Plasma dynamics of a two-frequency capacitive discharge in an Ar/Xe mixture
M. A. Bogdanova$^2$, D. G. Voloshin$^1$, A. V. Glotov$^2$, D. V. Lopaev$^1$, N. N. Sysoev$^2$, D. R. Shibanov$^1$
The spatiotemporal dynamics of the plasma of a symmetrical dual-frequency 81 MHz/1.76 MHz capacitive discharge under the influence of a low-frequency field of 1.76 MHz has been studied. Using the method of phase-resolved optical emission spectroscopy, the dynamics of the radiation intensity of argon and xenon in plasma was obtained. The electron energy distribution function at the center of the discharge was measured using a Langmuir probe and the electron density was measured using a microwave probe. The main result is the dynamics of the intensity ratios of the selected argon and xenon lines depending on different conditions: at pressures of 40, 200 and 400 mTorr, LF voltage amplitude of 100, 200 and 400 V, input power at 81 MHz of 3 W and 15 W. The dynamics of high-energy electrons is studied based on a two-temperature approximation of the electron energy distribution function.
Show AbstractBehavior of the geomagnetic field during reversals and excursions
Behavior of the geomagnetic field during reversals and excursions
M. Yu. Reshetnyak
On the basis of the three-dimensional geodynamo model, it is shown that at small amplitudes of heat sources during reversals and excursions of the geomagnetic field, attenuation of not only the dipole magnetic field, but also the field of high harmonics is observed. In this scenario, the Earth's magnetosphere may be significantly smaller than previously expected, and the amount of radiation penetrating the Earth may be correspondingly greater.
Show AbstractA model of surface nanorelief formation under gas cluster ion beam irradiation
A model of surface nanorelief formation under gas cluster ion beam irradiation
D. R. Bessmertniy, A. E. Ieshkin
A model for the evolution of surface nanorelief under irradiation with gas cluster ions is proposed. The model is based on consideration of individual collisions of clusters with a surface. The amount of substance sputtered from the collision area and the efficiency of its redeposition onto other surface elements are determined. The performance of the model is shown when compared with experimental data. The stages of smoothing of a harmonic relief are studied. A new measure of the effectiveness of surface smoothing is proposed.
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