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A highly sensitive method for infrared radiation detection based on thermal resonance in an active bolometer is set forth. An active bolometer is a self-oscillating system consisting of an IR-sensitive cell in a feedback circuit of an adjustable proportional controller. The analysis of an active bolometer autonomous (dark) dynamics reveals that with a generalized gain factor A variation the system evolves from relaxation type towards oscillating and self-oscillating type. When A=Ac, where Ac is a critical value of the generalized gain factor A, the steady state loses stability through self-excited thermal oscillations. The resonance in a system weakly perturbed by IR radiation modulated at self-oscillation frequency q0[1+exp(iωct)] is considered. It is shown that in a small precritical vicinity =(A−Ac)/Ac of the gain factor the amplitude of forced thermal oscillations is proportional to q0/Ac. The D* calculation reveals that the detection power of a passive (A=0) bolometer increases with feedback introduction by a factor of 1/||. The detection powers of feasible versions of an active bolometer are compared. 相似文献
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A. D. Vasil’ev N. N. Golovnev M. S. Molokeev T. D. Churilov 《Journal of Structural Chemistry》2005,46(2):363-370
Synthesis of a complex formed by ciprofloxacin (cfH) and copper(II) chloride is described; its crystal structure is reported and analyzed in comparison to related compounds. The obtained compound (cfH3)CuCl4·H2O (cfH 3 2+ — double protonated cfH molecule) crystallizes as platelets of P21/c symmetry having the unit cell parameters a = 13.491(1) Å, b = 11.0459(7) Å, c = 16.299(1) Å; β = 111.392(7)°. Carbonyl oxygen O(1) is protonated, and hydrogen atom combined with it forms an intramolecular hydrogen bond with carboxylic O(2) oxygen (O(1)?O(2) = 2.642(5) Å). Terminal nitrogen atom N(3) of the piperazinyl group is also protonated, and two its hydrogen atoms participate in hydrogen bonds of N-H?Cl type. The structure also has hydrogen bonds O-H?O, O-H?Cl with the participation of water molecules which occupy hydrophilic channels. Molecular ions cfH 3 2+ make couples with intrapair π?π interactions. 相似文献
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N. V. Bulina É. A. Petrakovskaya A. S. Fedorov G. N. Churilov 《Physics of the Solid State》2007,49(3):599-602
Fullerenes containing manganese and iron atoms are synthesized in a high-frequency carbonhelium plasma at atmospheric pressure. The electron paramagnetic resonance (EPR) spectrum of the synthesized compound contains not only lines attributed to iron atoms but also the lines of a manganese ion pair with an additional hyperfine structure. The latter lines are assigned to the endohedral complex Mn2@Cn (n > 70). The possible existence of these structures is evaluated from quantum-chemical calculations of the optimum geometry of the endothedral fullerene Mn2@C84 with C 2v symmetry. It is found that the manganese atoms are spaced ~2.72 Å apart at the center of the molecule. 相似文献
5.
The spectrum of xenon excited in a low-inductance vacuum spark was photographed at high resolution in the region of 9.5-15.5 nm. The observed transitions were identified as belonging to ions from Xe8+ to Xe13+. In the region of importance for extreme-ultraviolet lithography around 13.4 nm, the strongest lines were identified as 4d8-4d7 5p transitions in Xe10+. The identifications were made by use of energy parameters extrapolated along the isoelectronic sequence. 相似文献
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I. V. Osipova I. A. Ryabkov N. G. Vnukova N. V. Bulina G. N. Churilov 《Journal of Applied Spectroscopy》2007,74(1):156-158
We present a design for a dual-jet arc plasmatron operating at a frequency of 66 kHz in an argon flow at atmospheric pressure.
We present the results of determination of the temperature, electron concentration, and electrode erosion obtained by atomic
emission spectral analysis. The proposed convenient design for a dualjet plasmatron and the low erosion of the copper electrodes
in the plasma make it possible to use it for medical purposes.
Report given at the Fifth International Conference on Plasma Physics and Plasma Technologies (PPPT-5), 18–22 September 2006,
Minsk, Belarus.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 1, pp. 139–140, January–February, 2007. 相似文献
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S. M. Churilov 《Journal of Experimental and Theoretical Physics》2002,94(6):1103-1105
The possibility of waveguide propagation of Alfvén waves in an inhomogeneous plasma only through dissipation without dispersion is demonstrated. 相似文献
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A. M. Orlov I. O. Yavtushenko M. V. Churilov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2010,4(5):831-835
The adsorption and kinetic processes of the formation of gas bubbles passivating the surface during polarization of copper
and graphite electrodes in 1% aqueous solution of sulfuric acid have been investigated. Three stages of the process related
to the recharging of the double electric layer—adsorption accumulation of the gas escaping from the surface, the critical
nucleation of the gas bubbles, and their subsequent growth—have been revealed, distinguished, and quantitatively estimated.
It has been shown that potential leveling at the steady-state value specified by the Tafel equation is unambiguously associated
with achievement of the limiting surface area screened by the gas bubbles for each particular current density. The surface
diffusion constants D
H = (1.5–4.4) × 10−4 and (0.1–3.8) × 10−5 cm2/s of hydrogen on copper and graphite, respectively, and D
O = (1.8–4.5) × 10−7 cm2/s of oxygen on graphite during the motion toward the drain (the gas bubbles) have been calculated. 相似文献