Register of the human brain acoustic area spectrum

Last years, there were developed methods based on the human brain and body acoustic signals application. We consider human brain micro vibrations as an ancient, highly reliable, relatively rapid channel of the central nervous system with all the organism cells and structures. There is offered a method of the human brain acoustic area spectrum analysis and registration. Experimental sample “Register of the human brain micro vibrations spectrum is developed. The model of the human brain acoustic area generation is offered – neurovascular reflex and related with human brain blood vessels smooth muscularity nerve cells metabolism. In comparison with classical EEG, it is demonstrated that acoustic encephalogram also reflects human brain neuroreflex activity. Piezoelectric sensors, which feature in silicone membrane existence, are investigated. Such type of construction allowed to register human brain mechanical vibrations in the gamut from 0.1 up to 27 Hz. Spectral analysis is specific in that signal integration time is 160 seconds. Meanwhile, 12600 spectral harmonics of the human brain reticular activating system were reliably extracted. For convenience, all the acoustic area spectrum of the human brain was shrunk into segmental frame of reference which is frequency structured matrix of functional conditions multiplicity “multiple arousal” of 24х625 frequency cells size. All the developed technologies and device might be used for the organism adaptation estimations, psycho-emotional conditions estimations and functional-topical diagnosis of the internal parts of the human body.

Measurement of tropospheric HO2 radical using fluorescence assay by gas expansion with low interferences

<p>    An instrument to detect atmospheric HO<sub>2</sub> radicals using fluorescence assay by gas expansion (FAGE) technique has been developed. HO<sub>2</sub> is measured by reaction with NO to form OH and subsequent detection of OH by laser-induced fluorescence at low pressure. The system performance has been improved by optimizing the expansion distance and pressure, and the influence factors of HO<sub>2 </sub>conversion efficiency are also studied. The interferences of RO<sub>2</sub> radicals produced from OH plus some typical organic compounds were investigated by determining the conversion efficiency of RO<sub>2</sub> to OH during the measurement of HO<sub>2</sub>. The dependence of the conversion of HO<sub>2</sub> on NO concentration was investigated, and low HO<sub>2</sub> conversion efficiency was selected to realize the ambient HO<sub>2</sub> measurement, where the conversion efficiency of RO<sub>2</sub> derived by propane, ethene, isoprene and methanol to OH has been reduced to no more than 6%. Furthermore, no significant interferences from PM<sub>2.5</sub> and NO were found in the ambient HO<sub>2</sub> measurement. The detection limits for HO<sub>2</sub> (S/N=2) are estimated to 4.8×10<sup>5</sup> cm<sup>-3</sup> and 1.1×10<sup>6</sup> cm<sup>-3 </sup>(the conversion efficiency of HO<sub>2</sub> to OH, =20%) under night and noon conditions, with 60s signal integration time. The instrument was successfully deployed during STORM-2018 field campaign at Shenzhen graduate school of Peking University. The diurnal variation of HOx concentration shows that the OH maximum concentration of those days is about 5.5×10<sup>6 </sup>cm<sup>-3 </sup>appearing around 12:00, while the HO<sub>2</sub> maximum concentration is about 5.0×10<sup>8 </sup>cm<sup>-3 </sup>appearing around 13:30.</p>

The Energy Response of Calorimeters

This chapter deals with the signals produced by particles that are being absorbed in a calorimeter. The calorimeter response is defined as the average signal produced per unit energy deposited in this absorption process, for example in terms of picoCoulombs per GeV. Defined in this way, a linear calorimeter has a constant response. Typically, the response of the calorimeter depends on the type of particle absorbed in it. Also, most calorimeters are non-linear for hadronic shower detection. This is the essence of the so-called non-compensation problem, which has in practice major consequences for the performance of calorimeters. The origins of this problem, and its possible solutions are described. The roles of the sampling fraction, the sampling frequency, the signal integration time and the choice of the absorber and active materials are examined in detail. Important parameters, such as the e/mip and e/h values, are defined and methods to determine their value are described.

The improvement of the detection power of a U-shaped DC plasma

Optimization of the operating parameters of U-shpaed DC arc plasma and spectrometer parameters has been undertaken to explore the possibilities of improving its detection power. It is demonstrated, with a U-shaped arc as an example, that the limits of detection, in addition to well-defined parameters as described by Boumans1,2 and Winge,3 depend on the signal integration time. It is shown that with increasing integration time, the limits of detection are decreased within some limits and that the precision and concentration sensitivity are improved as well. A mathematical expression for the dependence of the detection limit on the integration time is presented. To increase the reliability of the measurement of the mentioned parameters, the working conditions were optimized for the following analytes: Ag, Al, Au, Cr, Fe, Mn, Ni, Pb, Pd, Pt, and V. The obtained limits of detection are comparable or better than those obtained by ICP for the elements studied. It was estimed that the possibility exists for their further improvement up to 10 times.