[Harmonic imaging analysis for assessment of morphological changes in mini-pig alveolar bone by normal and increased functional load].

The aim of the study was to reveal the mastication forces effect on the microstructure of mandible bone tissue of mini-pigs by Fouirier harmonic imaging analysis of bone sections images of back scattered electrons and assessment of calcium and phosphorous distribution maps obtained by roentgenofluorescence technique. The results showed that by higher functional loads not only the total content of mineral elements in the bone matrix increased but also the of the low-frequency harmonics in the image spectrum indicating structural heterogeneity decrease in bone mineralization.

[Use of Fourier analysis in hystomorphometry].

The mandible alveolar bone tissue of mini-pig was evaluated by means of radiospectral analysis. Fourier analysis of mineral content distribution in bone slices showed that loss of masticatory load leads to focal demineralization. With time the demineralization foci increased in amount, not in size.

[Experimental substantiation of parameters and strength characteristics of new endodontic-endoosseous implant construction].

Postoperative tooth stump is not able to endure usual functional loads adequately that leads to enhanced resorption of bone tissues surrounding root and loss of the tooth. Based on math computer simulation of mode of deformation of biomechanical model "metal-ceramic construction--endodontic-endoosseous implant (EEI)--stump of operated tooth--bone tissue of the jaw" new domestic EEI parameters were elaborated which improved greatly biomechanical properties of tooth with operated roots. Strength characteristics of new EEI were studied. A set of instruments for EEI was developed.

Temperature dependence of laser-induced fluorescence of nitric oxide in laminar premixed atmospheric-pressure flames.

The temperature dependence of laser-induced NO A (2)?(+)-X (2)? fluorescence in the hot gases of natural gas-air flames, seeded with known quantities of NO, has been determined experimentally by means of a difference method. The flame temperature at three fixed equivalence ratios was changed when the mixture velocity was varied through a water-cooled, flat-flame burner and was measured by coherent anti-Stokes Raman spectroscopy. When the possible reburning of part of the seeded NO is allowed for, the results in the range 1700-2150 K are best described by the temperature dependence obtained from a model in which quenching corrections are neglected, as in the case of a saturated two-level system, when millijoule pulse energies are used. Measurements of the fluorescence intensity at constant seed concentration as a function of equivalence ratio between 0.75 and 1.3 also indicate that quenching corrections are unnecessary under these excitation conditions. Using the measured intensities of the seeded flame as a calibration factor, we determined the absolute NO concentrations as functions of the equivalence ratio at 1 cm above the burner. The results indicate that, with the calibration method presented here, a relative accuracy of 5% should be obtainable.

Analysis of laser-induced-fluorescence carbon monoxide measurements in turbulent nonpremixed flames.

The influence of fluctuating concentrations and temperature on the laser-induced-fluorescence (LIF) measurement of CO in turbulent flames is described, under conditions in which the fluorescence and the temperature are measured independently. The analysis shows that correlations between CO concentration and temperature can bias the averaged mole fraction extracted from LIF measurements. The magnitude of the bias can exceed the order of the average CO mole fraction. Further, LIF measurements of CO concentrations in a turbulent, nonpremixed, natural gas flame are described. The averaged CO mole fractions are derived from the fluorescence measurements by the use of flame temperatures independently measured by coherent anti-Stokes Raman spectroscopy. Analysis of the fluctuations in measured temperature and fluorescence indicates that temperature and CO concentrations in flame regions with intensive mixing are indeed correlated. In the flame regions where burnout of CO has ceased, the LIF measurements of the CO mole fraction correspond to the probe measurements in exhaust.